diff --git a/xo-reader2/include/xo/reader2/ParserStateMachine.hpp b/xo-reader2/include/xo/reader2/ParserStateMachine.hpp
index 5a7a833f..fb276bd0 100644
--- a/xo-reader2/include/xo/reader2/ParserStateMachine.hpp
+++ b/xo-reader2/include/xo/reader2/ParserStateMachine.hpp
@@ -7,6 +7,7 @@
 
 #include "ParserResult.hpp"
 #include <xo/expression2/DVariable.hpp>
+#include <xo/expression2/StringTable.hpp>
 #include <xo/tokenizer2/Token.hpp>
 #include <xo/alloc2/Allocator.hpp>
 #include <xo/arena/DArena.hpp>
@@ -30,9 +31,11 @@ namespace xo {
             using AAllocator = xo::mm::AAllocator;
             using ArenaConfig = xo::mm::ArenaConfig;
             using DArena = xo::mm::DArena;
+            using size_type = std::size_t;
 
         public:
             ParserStateMachine(const ArenaConfig & config,
+                               size_type max_stringtable_capacity,
                                obj<AAllocator> expr_alloc);
 
             /** @defgroup scm-parserstatemachine-accessors accessor methods **/
@@ -129,6 +132,10 @@ namespace xo {
 
         private:
 
+            /** Table containing interned strings + symbols.
+             **/
+            StringTable stringtable_;
+
             /** Arena for internal parsing stack.
              *  Must be owned exclusively because destructively
              *  modified as parser completes parsing of each sub-expression
diff --git a/xo-reader2/include/xo/reader2/SchematikaParser.hpp b/xo-reader2/include/xo/reader2/SchematikaParser.hpp
index 2f7d6d95..81115239 100644
--- a/xo-reader2/include/xo/reader2/SchematikaParser.hpp
+++ b/xo-reader2/include/xo/reader2/SchematikaParser.hpp
@@ -167,6 +167,7 @@ namespace xo {
              *  @p debug_flag  true to enable debug logging
              **/
             SchematikaParser(const ArenaConfig & config,
+                             size_t max_stringtable_capacity,
                              obj<AAllocator> expr_alloc,
                              bool debug_flag);
 
diff --git a/xo-reader2/src/reader2/ParserStateMachine.cpp b/xo-reader2/src/reader2/ParserStateMachine.cpp
index 2e61be95..1766f652 100644
--- a/xo-reader2/src/reader2/ParserStateMachine.cpp
+++ b/xo-reader2/src/reader2/ParserStateMachine.cpp
@@ -17,11 +17,14 @@ namespace xo {
 
     namespace scm {
         ParserStateMachine::ParserStateMachine(const ArenaConfig & config,
+                                               size_type max_stringtable_capacity,
                                                obj<AAllocator> expr_alloc)
-            : parser_alloc_{DArena::map(config)},
+            : stringtable_{max_stringtable_capacity},
+              parser_alloc_{DArena::map(config)},
               expr_alloc_{expr_alloc},
               debug_flag_{config.debug_flag_}
         {
+
         }
 
         bool
diff --git a/xo-reader2/src/reader2/SchematikaParser.cpp b/xo-reader2/src/reader2/SchematikaParser.cpp
index 442da75e..ac2d4520 100644
--- a/xo-reader2/src/reader2/SchematikaParser.cpp
+++ b/xo-reader2/src/reader2/SchematikaParser.cpp
@@ -19,9 +19,10 @@ namespace xo {
         // ----- SchematikaParser -----
 
         SchematikaParser::SchematikaParser(const ArenaConfig & config,
+                                           size_t max_stringtable_capacity,
                                            obj<AAllocator> expr_alloc,
                                            bool debug_flag)
-            : psm_{config, expr_alloc},
+            : psm_{config, max_stringtable_capacity, expr_alloc},
               debug_flag_{debug_flag}
         {
         }
diff --git a/xo-reader2/utest/SchematikaParser.test.cpp b/xo-reader2/utest/SchematikaParser.test.cpp
index 194a6d13..259336cf 100644
--- a/xo-reader2/utest/SchematikaParser.test.cpp
+++ b/xo-reader2/utest/SchematikaParser.test.cpp
@@ -27,7 +27,7 @@ namespace xo {
             DArena expr_arena = DArena::map(config);
             obj<AAllocator> expr_alloc = with_facet<AAllocator>::mkobj(&expr_arena);
 
-            SchematikaParser parser(config, expr_alloc, false /*debug_flag*/);
+            SchematikaParser parser(config, 4096, expr_alloc, false /*debug_flag*/);
 
             REQUIRE(parser.debug_flag() == false);
             REQUIRE(parser.is_at_toplevel() == true);
@@ -42,7 +42,7 @@ namespace xo {
             DArena expr_arena = DArena::map(config);
             obj<AAllocator> expr_alloc = with_facet<AAllocator>::mkobj(&expr_arena);
 
-            SchematikaParser parser(config, expr_alloc, false /*debug_flag*/);
+            SchematikaParser parser(config, 4096, expr_alloc, false /*debug_flag*/);
 
             parser.begin_interactive_session();
 
@@ -60,7 +60,7 @@ namespace xo {
             DArena expr_arena = DArena::map(config);
             obj<AAllocator> expr_alloc = with_facet<AAllocator>::mkobj(&expr_arena);
 
-            SchematikaParser parser(config, expr_alloc, false /*debug_flag*/);
+            SchematikaParser parser(config, 4096, expr_alloc, false /*debug_flag*/);
 
             parser.begin_batch_session();
 
@@ -78,7 +78,7 @@ namespace xo {
             DArena expr_arena = DArena::map(config);
             obj<AAllocator> expr_alloc = with_facet<AAllocator>::mkobj(&expr_arena);
 
-            SchematikaParser parser(config, expr_alloc, false /*debug_flag*/);
+            SchematikaParser parser(config, 4096, expr_alloc, false /*debug_flag*/);
 
             parser.begin_batch_session();
 
@@ -113,7 +113,7 @@ namespace xo {
             DArena expr_arena = DArena::map(config);
             obj<AAllocator> expr_alloc = with_facet<AAllocator>::mkobj(&expr_arena);
 
-            SchematikaParser parser(config, expr_alloc, false /*debug_flag*/);
+            SchematikaParser parser(config, 4096, expr_alloc, false /*debug_flag*/);
 
             parser.begin_interactive_session();