diff --git a/xo-interpreter2/CMakeLists.txt b/xo-interpreter2/CMakeLists.txt
index 26124a21..0b5431ba 100644
--- a/xo-interpreter2/CMakeLists.txt
+++ b/xo-interpreter2/CMakeLists.txt
@@ -103,6 +103,32 @@ xo_add_genfacetimpl(
 
 # ----------------------------------------------------------------
 
+# note: manual target; generated code committed to git
+xo_add_genfacetimpl(
+    TARGET xo-interpreter2-facetimpl-gcobject-vsmifelsecontframe
+    FACET_PKG xo_gc
+    FACET GCObject
+    REPR VsmIfElseContFrame
+    INPUT idl/IGCObject_DVsmIfElseContFrame.json5
+    OUTPUT_HPP_DIR include/xo/interpreter2
+    OUTPUT_IMPL_SUBDIR ifelse
+    OUTPUT_CPP_DIR src/interpreter2
+)
+
+# note: manual target; generated code committed to git
+xo_add_genfacetimpl(
+    TARGET xo-interpreter2-facetimpl-printable-vsmifelsecontframe
+    FACET_PKG xo_printable2
+    FACET Printable
+    REPR VsmIfElseContFrame
+    INPUT idl/IPrintable_DVsmIfElseContFrame.json5
+    OUTPUT_HPP_DIR include/xo/interpreter2
+    OUTPUT_IMPL_SUBDIR ifelse
+    OUTPUT_CPP_DIR src/interpreter2
+)
+
+# ----------------------------------------------------------------
+
 # note: manual target; generated code committed to git
 xo_add_genfacetimpl(
     TARGET xo-interpreter2-facetimpl-gcobject-vsmseqcontframe
diff --git a/xo-interpreter2/idl/IGCObject_DVsmIfElseContFrame.json5 b/xo-interpreter2/idl/IGCObject_DVsmIfElseContFrame.json5
new file mode 100644
index 00000000..0f78bb6d
--- /dev/null
+++ b/xo-interpreter2/idl/IGCObject_DVsmIfElseContFrame.json5
@@ -0,0 +1,15 @@
+{
+    mode: "implementation",
+    includes: [
+        "<xo/gc/GCObject.hpp>",
+        "<xo/alloc2/Allocator.hpp>"
+    ],
+    local_types: [ ],
+    namespace1: "xo",
+    namespace2: "scm",
+    facet_idl: "idl/GCObject.json5",
+    brief: "provide AGCObject interface for DVsmIfElseContFrame",
+    using_doxygen: true,
+    repr: "DVsmIfElseContFrame",
+    doc: [ "implement AGCObject for DVsmIfElseContFrame" ],
+}
diff --git a/xo-interpreter2/idl/IPrintable_DVsmIfElseContFrame.json5 b/xo-interpreter2/idl/IPrintable_DVsmIfElseContFrame.json5
new file mode 100644
index 00000000..d3d63c4d
--- /dev/null
+++ b/xo-interpreter2/idl/IPrintable_DVsmIfElseContFrame.json5
@@ -0,0 +1,13 @@
+{
+    mode: "implementation",
+    includes: [ "<xo/printable2/Printable.hpp>",
+                "<xo/printable2/detail/IPrintable_Xfer.hpp>" ],
+    local_types: [ ],
+    namespace1: "xo",
+    namespace2: "scm",
+    facet_idl: "idl/Printable.json5",
+    brief: "provide APrintable interface for DVsmIfElseContFrame",
+    using_doxygen: true,
+    repr: "DVsmIfElseContFrame",
+    doc: [ "implement APrintable for DVsmIfElseContFrame" ],
+}
diff --git a/xo-interpreter2/include/xo/interpreter2/DVsmIfElseContFrame.hpp b/xo-interpreter2/include/xo/interpreter2/DVsmIfElseContFrame.hpp
new file mode 100644
index 00000000..3d4ace12
--- /dev/null
+++ b/xo-interpreter2/include/xo/interpreter2/DVsmIfElseContFrame.hpp
@@ -0,0 +1,82 @@
+/** @file DVsmIfElseContFrame.hpp
+ *
+ *  @author Roland Conybeare, Feb 2026
+ **/
+
+#pragma once
+
+#include "VsmInstr.hpp"
+#include <xo/expression2/IfElseExpr.hpp>
+#include <xo/gc/GCObject.hpp>
+
+namespace xo {
+    namespace scm {
+        /** @brief saved VSM state during evaluation of a SequenceExpr
+         **/
+        class DVsmIfElseContFrame {
+        public:
+            using ACollector = xo::mm::ACollector;
+            using AAllocator = xo::mm::AAllocator;
+            using AGCObject = xo::mm::AGCObject;
+            using ppindentinfo = xo::print::ppindentinfo;
+
+        public:
+            /** @defgroup scm-vsmevalsequenceframe-ctors constructors **/
+            ///@{
+
+            DVsmIfElseContFrame(obj<AGCObject> parent,
+                                VsmInstr cont,
+                                DIfElseExpr * ifelse_expr);
+
+            /** create instance using memory from allocator @p mm **/
+            static DVsmIfElseContFrame * make(obj<AAllocator> mm,
+                                              obj<AGCObject> parent,
+                                              VsmInstr cont,
+                                              DIfElseExpr * ifelse_expr);
+
+            ///@}
+            /** @defgroup scm-vsmevalsequenceframe-access-methods access methods **/
+            ///@{
+
+            obj<AGCObject> parent() const noexcept { return parent_; }
+            VsmInstr cont() const noexcept { return cont_; }
+            DIfElseExpr * ifelse_expr() const noexcept { return ifelse_expr_; }
+
+            ///@}
+            /** @defgroup scm-vsmevalsequenceframe-general-methods general methods **/
+            ///@{
+
+            ///@}
+            /** @defgroup scm-vsmevalsequenceframe-gcobject-facet gcobject facet **/
+            ///@{
+
+            std::size_t shallow_size() const noexcept;
+            DVsmIfElseContFrame * shallow_copy(obj<AAllocator> mm) const noexcept;
+            std::size_t forward_children(obj<ACollector> gc) noexcept;
+
+            ///@}
+            /** @defgrouop scm-vsmseqcontframe-printable-facet printable facet **/
+            ///@{
+
+            bool pretty(const ppindentinfo & ppii) const noexcept;
+
+            ///@}
+            
+        private:
+            /** @defgroup scm-vsmevalsequenceframe-members member variables **/
+            ///@{
+
+            /** saved VSM stack; restore when this frame consumed **/
+            obj<AGCObject> parent_;
+            /** saved continuation; restore when this frame consumed **/
+            VsmInstr cont_;
+            /** saved expr. evaluate elements of this sequence in order **/
+            DIfElseExpr * ifelse_expr_ = nullptr;
+
+            ///@}
+        };
+
+    } /*namespace scm*/
+} /*namespace xo*/
+
+/* end DVsmIfElseContFrame.hpp */
diff --git a/xo-interpreter2/include/xo/interpreter2/VirtualSchematikaMachine.hpp b/xo-interpreter2/include/xo/interpreter2/VirtualSchematikaMachine.hpp
index ce412391..b809a09d 100644
--- a/xo-interpreter2/include/xo/interpreter2/VirtualSchematikaMachine.hpp
+++ b/xo-interpreter2/include/xo/interpreter2/VirtualSchematikaMachine.hpp
@@ -187,6 +187,11 @@ namespace xo {
              **/
             void _do_apply_cont_op();
 
+            /** proceed with if- or else- branch of an if-else expression
+             *  after evaluating test condition
+             **/
+            void _do_ifelse_cont_op();
+
             /** loop continuation after evaluating element of a SequenceExpr **/
             void _do_seq_cont_op();
 
diff --git a/xo-interpreter2/include/xo/interpreter2/VsmIfElseContFrame.hpp b/xo-interpreter2/include/xo/interpreter2/VsmIfElseContFrame.hpp
new file mode 100644
index 00000000..a0494ddf
--- /dev/null
+++ b/xo-interpreter2/include/xo/interpreter2/VsmIfElseContFrame.hpp
@@ -0,0 +1,12 @@
+/** @file VsmIfElseContFrame.hpp
+ *
+ *  @author Roland Conybeare, Feb 2026
+ **/
+
+#pragma once
+
+#include "DVsmIfElseContFrame.hpp"
+#include "ifelse/IGCObject_DVsmIfElseContFrame.hpp"
+#include "ifelse/IPrintable_DVsmIfElseContFrame.hpp"
+
+/* end VsmIfElseContFrame.hpp */
diff --git a/xo-interpreter2/include/xo/interpreter2/VsmInstr.hpp b/xo-interpreter2/include/xo/interpreter2/VsmInstr.hpp
index d7444b86..1279f8b7 100644
--- a/xo-interpreter2/include/xo/interpreter2/VsmInstr.hpp
+++ b/xo-interpreter2/include/xo/interpreter2/VsmInstr.hpp
@@ -13,14 +13,21 @@ namespace xo {
         public:
             explicit VsmInstr(vsm_opcode oc) : opcode_{oc} {}
 
+            // instructions
+
             static VsmInstr c_halt;
             static VsmInstr c_eval;
 
             static VsmInstr c_apply;
             static VsmInstr c_evalargs;
-            /** proceed to continuation after an ApplyExpr **/
+            /** restore VSM state for continuation of an apply expression **/
             static VsmInstr c_apply_cont;
 
+            /** proceed to branch of if-else expression after evaluating
+             *  test condition
+             **/
+            static VsmInstr c_ifelse_cont;
+
             /** loop to evaluate members of a SequenceExpr **/
             static VsmInstr c_seq_cont;
 
diff --git a/xo-interpreter2/include/xo/interpreter2/VsmOpcode.hpp b/xo-interpreter2/include/xo/interpreter2/VsmOpcode.hpp
index 2a277a49..e1000cb3 100644
--- a/xo-interpreter2/include/xo/interpreter2/VsmOpcode.hpp
+++ b/xo-interpreter2/include/xo/interpreter2/VsmOpcode.hpp
@@ -28,11 +28,14 @@ namespace xo {
              **/
             evalargs,
 
-            /** Coda to restore vsm registers (local_env, stack, cont)
+            /** continuation to restore vsm registers (local_env, stack, cont)
              *  after invoking a closure
              **/
             apply_cont,
 
+            /** continuation to act on a branch **/
+            ifelse_cont,
+
             /** Loop over elements of a SequenceExpr **/
             seq_cont,
 
@@ -55,3 +58,4 @@ namespace xo {
 } /*namespace xo*/
 
 /* end VsmOpcode.hpp */
+
diff --git a/xo-interpreter2/include/xo/interpreter2/ifelse/IGCObject_DVsmIfElseContFrame.hpp b/xo-interpreter2/include/xo/interpreter2/ifelse/IGCObject_DVsmIfElseContFrame.hpp
new file mode 100644
index 00000000..293dd70d
--- /dev/null
+++ b/xo-interpreter2/include/xo/interpreter2/ifelse/IGCObject_DVsmIfElseContFrame.hpp
@@ -0,0 +1,67 @@
+/** @file IGCObject_DVsmIfElseContFrame.hpp
+ *
+ *  Generated automagically from ingredients:
+ *  1. code generator:
+ *       [xo-facet/codegen/genfacet]
+ *     arguments:
+ *       --input [idl/IGCObject_DVsmIfElseContFrame.json5]
+ *  2. jinja2 template for abstract facet .hpp file:
+ *       [iface_facet_repr.hpp.j2]
+ *  3. idl for facet methods
+ *       [idl/IGCObject_DVsmIfElseContFrame.json5]
+ **/
+
+#pragma once
+
+#include "GCObject.hpp"
+#include <xo/gc/GCObject.hpp>
+#include <xo/alloc2/Allocator.hpp>
+#include "DVsmIfElseContFrame.hpp"
+
+namespace xo { namespace scm { class IGCObject_DVsmIfElseContFrame; } }
+
+namespace xo {
+    namespace facet {
+        template <>
+        struct FacetImplementation<xo::mm::AGCObject,
+                                   xo::scm::DVsmIfElseContFrame>
+        {
+            using ImplType = xo::mm::IGCObject_Xfer
+              <xo::scm::DVsmIfElseContFrame,
+               xo::scm::IGCObject_DVsmIfElseContFrame>;
+        };
+    }
+}
+
+namespace xo {
+    namespace scm {
+        /** @class IGCObject_DVsmIfElseContFrame
+         **/
+        class IGCObject_DVsmIfElseContFrame {
+        public:
+            /** @defgroup scm-gcobject-dvsmifelsecontframe-type-traits **/
+            ///@{
+            using size_type = xo::mm::AGCObject::size_type;
+            using AAllocator = xo::mm::AGCObject::AAllocator;
+            using ACollector = xo::mm::AGCObject::ACollector;
+            using Copaque = xo::mm::AGCObject::Copaque;
+            using Opaque = xo::mm::AGCObject::Opaque;
+            ///@}
+            /** @defgroup scm-gcobject-dvsmifelsecontframe-methods **/
+            ///@{
+            // const methods
+            /** memory consumption for this instance **/
+            static size_type shallow_size(const DVsmIfElseContFrame & self) noexcept;
+            /** copy instance using allocator **/
+            static Opaque shallow_copy(const DVsmIfElseContFrame & self, obj<AAllocator> mm) noexcept;
+
+            // non-const methods
+            /** during GC: forward immdiate children **/
+            static size_type forward_children(DVsmIfElseContFrame & self, obj<ACollector> gc) noexcept;
+            ///@}
+        };
+
+    } /*namespace scm*/
+} /*namespace xo*/
+
+/* end */
\ No newline at end of file
diff --git a/xo-interpreter2/include/xo/interpreter2/ifelse/IPrintable_DVsmIfElseContFrame.hpp b/xo-interpreter2/include/xo/interpreter2/ifelse/IPrintable_DVsmIfElseContFrame.hpp
new file mode 100644
index 00000000..5f0e5a7b
--- /dev/null
+++ b/xo-interpreter2/include/xo/interpreter2/ifelse/IPrintable_DVsmIfElseContFrame.hpp
@@ -0,0 +1,62 @@
+/** @file IPrintable_DVsmIfElseContFrame.hpp
+ *
+ *  Generated automagically from ingredients:
+ *  1. code generator:
+ *       [xo-facet/codegen/genfacet]
+ *     arguments:
+ *       --input [idl/IPrintable_DVsmIfElseContFrame.json5]
+ *  2. jinja2 template for abstract facet .hpp file:
+ *       [iface_facet_repr.hpp.j2]
+ *  3. idl for facet methods
+ *       [idl/IPrintable_DVsmIfElseContFrame.json5]
+ **/
+
+#pragma once
+
+#include "Printable.hpp"
+#include <xo/printable2/Printable.hpp>
+#include <xo/printable2/detail/IPrintable_Xfer.hpp>
+#include "DVsmIfElseContFrame.hpp"
+
+namespace xo { namespace scm { class IPrintable_DVsmIfElseContFrame; } }
+
+namespace xo {
+    namespace facet {
+        template <>
+        struct FacetImplementation<xo::print::APrintable,
+                                   xo::scm::DVsmIfElseContFrame>
+        {
+            using ImplType = xo::print::IPrintable_Xfer
+              <xo::scm::DVsmIfElseContFrame,
+               xo::scm::IPrintable_DVsmIfElseContFrame>;
+        };
+    }
+}
+
+namespace xo {
+    namespace scm {
+        /** @class IPrintable_DVsmIfElseContFrame
+         **/
+        class IPrintable_DVsmIfElseContFrame {
+        public:
+            /** @defgroup scm-printable-dvsmifelsecontframe-type-traits **/
+            ///@{
+            using ppindentinfo = xo::print::APrintable::ppindentinfo;
+            using Copaque = xo::print::APrintable::Copaque;
+            using Opaque = xo::print::APrintable::Opaque;
+            ///@}
+            /** @defgroup scm-printable-dvsmifelsecontframe-methods **/
+            ///@{
+            // const methods
+            /** Pretty-printing support for this object.
+See [xo-indentlog/xo/indentlog/pretty.hpp] **/
+            static bool pretty(const DVsmIfElseContFrame & self, const ppindentinfo & ppii);
+
+            // non-const methods
+            ///@}
+        };
+
+    } /*namespace scm*/
+} /*namespace xo*/
+
+/* end */
\ No newline at end of file
diff --git a/xo-interpreter2/src/interpreter2/CMakeLists.txt b/xo-interpreter2/src/interpreter2/CMakeLists.txt
index 64e7dfe8..c21821e1 100644
--- a/xo-interpreter2/src/interpreter2/CMakeLists.txt
+++ b/xo-interpreter2/src/interpreter2/CMakeLists.txt
@@ -20,6 +20,10 @@ set(SELF_SRCS
     IGCObject_DVsmApplyClosureFrame.cpp
     IPrintable_DVsmApplyClosureFrame.cpp
 
+    DVsmIfElseContFrame.cpp
+    IGCObject_DVsmIfElseContFrame.cpp
+    IPrintable_DVsmIfElseContFrame.cpp
+
     DVsmSeqContFrame.cpp
     IGCObject_DVsmSeqContFrame.cpp
     IPrintable_DVsmSeqContFrame.cpp
diff --git a/xo-interpreter2/src/interpreter2/DVsmIfElseContFrame.cpp b/xo-interpreter2/src/interpreter2/DVsmIfElseContFrame.cpp
new file mode 100644
index 00000000..f47419e0
--- /dev/null
+++ b/xo-interpreter2/src/interpreter2/DVsmIfElseContFrame.cpp
@@ -0,0 +1,66 @@
+/** @file DVsmIfElseContFrame.cpp
+ *
+ *  @author Roland Conybeare, Feb 2026
+ **/
+
+#include "DVsmIfElseContFrame.hpp"
+
+namespace xo {
+    namespace scm {
+
+        DVsmIfElseContFrame::DVsmIfElseContFrame(obj<AGCObject> parent,
+                                                 VsmInstr cont,
+                                                 DIfElseExpr * ifelse_expr)
+                : parent_{parent},
+                  cont_{cont},
+                  ifelse_expr_{ifelse_expr}
+        {}
+
+        DVsmIfElseContFrame *
+        DVsmIfElseContFrame::make(obj<AAllocator> mm,
+                                    obj<AGCObject> parent,
+                                    VsmInstr cont,
+                                  DIfElseExpr * seq_expr)
+        {
+            void * mem = mm.alloc_for<DVsmIfElseContFrame>();
+
+            return new (mem) DVsmIfElseContFrame(parent, cont, seq_expr);
+        }
+
+        // gcobject facet
+
+        std::size_t
+        DVsmIfElseContFrame::shallow_size() const noexcept
+        {
+            return sizeof(*this);
+        }
+
+        DVsmIfElseContFrame *
+        DVsmIfElseContFrame::shallow_copy(obj<AAllocator> mm) const noexcept
+        {
+            return mm.std_copy_for<DVsmIfElseContFrame>(this);
+        }
+
+        std::size_t
+        DVsmIfElseContFrame::forward_children(obj<ACollector> gc) noexcept
+        {
+            gc.forward_inplace(&parent_);
+            gc.forward_inplace(&ifelse_expr_);
+
+            return this->shallow_size();
+        }
+
+        // printable facet
+
+        bool
+        DVsmIfElseContFrame::pretty(const ppindentinfo & ppii) const noexcept
+        {
+            return ppii.pps()->pretty_struct(ppii,
+                                             "DVsmIfElseContFrame",
+                                             refrtag("cont", cont_));
+        }
+
+    } /*namespace scm*/
+} /*namespace xo*/
+
+/* end DVsmIfElseContFrame.cpp */
diff --git a/xo-interpreter2/src/interpreter2/IGCObject_DVsmIfElseContFrame.cpp b/xo-interpreter2/src/interpreter2/IGCObject_DVsmIfElseContFrame.cpp
new file mode 100644
index 00000000..ba66cd8d
--- /dev/null
+++ b/xo-interpreter2/src/interpreter2/IGCObject_DVsmIfElseContFrame.cpp
@@ -0,0 +1,39 @@
+/** @file IGCObject_DVsmIfElseContFrame.cpp
+ *
+ *  Generated automagically from ingredients:
+ *  1. code generator:
+ *       [xo-facet/codegen/genfacet]
+ *     arguments:
+ *       --input [idl/IGCObject_DVsmIfElseContFrame.json5]
+ *  2. jinja2 template for abstract facet .hpp file:
+ *       [iface_facet_any.hpp.j2]
+ *  3. idl for facet methods
+ *       [idl/IGCObject_DVsmIfElseContFrame.json5]
+**/
+
+#include "ifelse/IGCObject_DVsmIfElseContFrame.hpp"
+
+namespace xo {
+    namespace scm {
+        auto
+        IGCObject_DVsmIfElseContFrame::shallow_size(const DVsmIfElseContFrame & self) noexcept -> size_type
+        {
+            return self.shallow_size();
+        }
+
+        auto
+        IGCObject_DVsmIfElseContFrame::shallow_copy(const DVsmIfElseContFrame & self, obj<AAllocator> mm) noexcept -> Opaque
+        {
+            return self.shallow_copy(mm);
+        }
+
+        auto
+        IGCObject_DVsmIfElseContFrame::forward_children(DVsmIfElseContFrame & self, obj<ACollector> gc) noexcept -> size_type
+        {
+            return self.forward_children(gc);
+        }
+
+    } /*namespace scm*/
+} /*namespace xo*/
+
+/* end IGCObject_DVsmIfElseContFrame.cpp */
diff --git a/xo-interpreter2/src/interpreter2/IPrintable_DVsmIfElseContFrame.cpp b/xo-interpreter2/src/interpreter2/IPrintable_DVsmIfElseContFrame.cpp
new file mode 100644
index 00000000..e8afc908
--- /dev/null
+++ b/xo-interpreter2/src/interpreter2/IPrintable_DVsmIfElseContFrame.cpp
@@ -0,0 +1,28 @@
+/** @file IPrintable_DVsmIfElseContFrame.cpp
+ *
+ *  Generated automagically from ingredients:
+ *  1. code generator:
+ *       [xo-facet/codegen/genfacet]
+ *     arguments:
+ *       --input [idl/IPrintable_DVsmIfElseContFrame.json5]
+ *  2. jinja2 template for abstract facet .hpp file:
+ *       [iface_facet_any.hpp.j2]
+ *  3. idl for facet methods
+ *       [idl/IPrintable_DVsmIfElseContFrame.json5]
+**/
+
+#include "ifelse/IPrintable_DVsmIfElseContFrame.hpp"
+
+namespace xo {
+    namespace scm {
+        auto
+        IPrintable_DVsmIfElseContFrame::pretty(const DVsmIfElseContFrame & self, const ppindentinfo & ppii) -> bool
+        {
+            return self.pretty(ppii);
+        }
+
+
+    } /*namespace scm*/
+} /*namespace xo*/
+
+/* end IPrintable_DVsmIfElseContFrame.cpp */
diff --git a/xo-interpreter2/src/interpreter2/VirtualSchematikaMachine.cpp b/xo-interpreter2/src/interpreter2/VirtualSchematikaMachine.cpp
index d1b8eacb..f3473681 100644
--- a/xo-interpreter2/src/interpreter2/VirtualSchematikaMachine.cpp
+++ b/xo-interpreter2/src/interpreter2/VirtualSchematikaMachine.cpp
@@ -7,6 +7,7 @@
 #include "VsmApplyFrame.hpp"
 #include "VsmEvalArgsFrame.hpp"
 #include "VsmApplyClosureFrame.hpp"
+#include "VsmIfElseContFrame.hpp"
 #include "VsmSeqContFrame.hpp"
 #include "VsmRcx.hpp"
 #include "Closure.hpp"
@@ -14,6 +15,7 @@
 #include <xo/expression2/LambdaExpr.hpp>
 #include <xo/expression2/Constant.hpp>
 #include <xo/expression2/SequenceExpr.hpp>
+#include <xo/object2/Boolean.hpp>
 #include <xo/procedure2/RuntimeContext.hpp>
 //#include <xo/procedure2/SimpleRcx.hpp>
 #include <xo/gc/DX1Collector.hpp>
@@ -190,6 +192,9 @@ namespace xo {
             case vsm_opcode::apply_cont:
                 _do_apply_cont_op();
                 break;
+            case vsm_opcode::ifelse_cont:
+                _do_ifelse_cont_op();
+                break;
             case vsm_opcode::seq_cont:
                 _do_seq_cont_op();
                 break;
@@ -388,14 +393,26 @@ namespace xo {
         void
         VirtualSchematikaMachine::_do_eval_if_else_op()
         {
-            // not implemented
-            assert(false);
+            // control:
+            //   self -> eval(test) -> ifelse_cont -> eval(when_true)
+            //                                     -> eval(when_false)
+            
+            auto ifelse_expr = obj<AExpression,DIfElseExpr>::from(expr_);
+
+            obj<AGCObject,DVsmIfElseContFrame> ifelse_frame
+                (DVsmIfElseContFrame::make(mm_.to_op(),
+                                           stack_, cont_, ifelse_expr.data()));
+
+            this->stack_ = ifelse_frame;
+            this->cont_ = VsmInstr::c_ifelse_cont;
+            this->expr_ = ifelse_expr->test();
+            this->pc_ = VsmInstr::c_eval;
         }
 
         void
         VirtualSchematikaMachine::_do_eval_sequence_op()
         {
-            // assuming bump allocator:
+            // stack:
             //
             //   VsmEvalSequence
             //   v
@@ -640,6 +657,50 @@ namespace xo {
             this->pc_ = frame->cont();
         }
 
+        void
+        VirtualSchematikaMachine::_do_ifelse_cont_op()
+        {
+            // pre: result of evaluating test condition in value_ register
+
+            auto frame = obj<AGCObject,DVsmIfElseContFrame>::from(stack_);
+
+            assert(frame);
+            assert(value_.is_value());
+
+            auto flag = obj<AGCObject,DBoolean>::from(*value_.value());
+
+            if (flag.data()) {
+                obj<AExpression> next_expr;
+                {
+                    if (flag->value()) {
+                        // proceed with if-branch
+                        next_expr = frame->ifelse_expr()->when_true();
+                    } else {
+                        // proceed with else-branch
+                        next_expr = frame->ifelse_expr()->when_false();
+                    }
+                }
+
+                this->stack_ = frame->parent();
+                this->cont_ = frame->cont();
+                this->expr_ = next_expr;
+                this->pc_ = VsmInstr::c_eval;
+            } else {
+                auto error = DRuntimeError::make(mm_.to_op(),
+                                                 "_do_ifelse_cont_op",
+                                                 "expected boolean for test condition");
+                this->value_ = VsmResult(error);
+
+                // for now: halt VSM execution
+                // TODO: some combination of
+                // 1. emit stack trace 
+                // 2. go to debugger
+                // 3. have every vsm instruction check inputs for errors
+            
+                this->pc_ = VsmInstr::c_halt;
+            }
+        }
+
         void
         VirtualSchematikaMachine::_do_seq_cont_op()
         {
diff --git a/xo-interpreter2/src/interpreter2/VsmInstr.cpp b/xo-interpreter2/src/interpreter2/VsmInstr.cpp
index d1923cbd..b815c079 100644
--- a/xo-interpreter2/src/interpreter2/VsmInstr.cpp
+++ b/xo-interpreter2/src/interpreter2/VsmInstr.cpp
@@ -16,6 +16,7 @@ namespace xo {
             case vsm_opcode::apply: return "apply";
             case vsm_opcode::evalargs: return "evalargs";
             case vsm_opcode::apply_cont: return "apply_cont";
+            case vsm_opcode::ifelse_cont: return "ifelse_cont";
             case vsm_opcode::seq_cont: return "seq_cont";
             case vsm_opcode::N:
                 break;
@@ -39,6 +40,9 @@ namespace xo {
         VsmInstr
         VsmInstr::c_apply_cont = VsmInstr(vsm_opcode::apply_cont);
 
+        VsmInstr
+        VsmInstr::c_ifelse_cont = VsmInstr(vsm_opcode::ifelse_cont);
+        
         VsmInstr
         VsmInstr::c_seq_cont = VsmInstr(vsm_opcode::seq_cont);
     } /*namespace scm*/
diff --git a/xo-interpreter2/src/interpreter2/interpreter2_register_facets.cpp b/xo-interpreter2/src/interpreter2/interpreter2_register_facets.cpp
index 588419a2..dc9b31be 100644
--- a/xo-interpreter2/src/interpreter2/interpreter2_register_facets.cpp
+++ b/xo-interpreter2/src/interpreter2/interpreter2_register_facets.cpp
@@ -9,6 +9,7 @@
 #include "VsmApplyFrame.hpp"
 #include "VsmEvalArgsFrame.hpp"
 #include "VsmApplyClosureFrame.hpp"
+#include "VsmIfElseContFrame.hpp"
 #include "VsmSeqContFrame.hpp"
 #include "Primitive_gco_2_gco_gco.hpp"
 #include "Closure.hpp"
@@ -38,6 +39,7 @@ namespace xo {
             // +- VsmApplyFrame
             // +- VsmEvalArgsFrame
             // +- VsmApplyClosureFrame
+            // +- VsmIfElseContFrame
             // \- VsmSeqContFrame
 
             FacetRegistry::register_impl<AGCObject, DVsmApplyFrame>();
@@ -49,6 +51,9 @@ namespace xo {
             FacetRegistry::register_impl<AGCObject, DVsmApplyClosureFrame>();
             FacetRegistry::register_impl<APrintable, DVsmApplyClosureFrame>();
 
+            FacetRegistry::register_impl<AGCObject, DVsmIfElseContFrame>();
+            FacetRegistry::register_impl<APrintable, DVsmIfElseContFrame>();
+
             FacetRegistry::register_impl<AGCObject, DVsmSeqContFrame>();
             FacetRegistry::register_impl<APrintable, DVsmSeqContFrame>();
 
diff --git a/xo-interpreter2/utest/VirtualSchematikaMachine.test.cpp b/xo-interpreter2/utest/VirtualSchematikaMachine.test.cpp
index 960c1771..eb62267e 100644
--- a/xo-interpreter2/utest/VirtualSchematikaMachine.test.cpp
+++ b/xo-interpreter2/utest/VirtualSchematikaMachine.test.cpp
@@ -30,6 +30,7 @@ namespace xo {
     using xo::scm::VsmConfig;
     using xo::scm::VsmResultExt;
     using xo::scm::DClosure;
+    using xo::scm::DString;
     using xo::scm::DFloat;
     using xo::scm::DBoolean;
     using xo::scm::DInteger;
@@ -258,10 +259,10 @@ namespace xo {
 
             log && log(xtag("res.tseq", res.value()->_typeseq()));
 
-            auto x = obj<AGCObject,DBoolean>::from(*res.value());
+            auto x = obj<AGCObject,DString>::from(*res.value());
 
             REQUIRE(x);
-            REQUIRE(x.data()->value() == true);
+            REQUIRE(strcmp(x.data()->chars(), "equal") == 0);
 
             REQUIRE(res.remaining_.size() == 1);
             REQUIRE(*res.remaining_.lo() == '\n');