diff --git a/components/compiler/exprparser.cpp b/components/compiler/exprparser.cpp
index 12f63d3aa..79b6f3447 100644
--- a/components/compiler/exprparser.cpp
+++ b/components/compiler/exprparser.cpp
@@ -155,6 +155,25 @@ namespace Compiler
         popOperator();
     }
             
+    void ExprParser::parseArguments (const std::string& arguments, Scanner& scanner)
+    {
+        ExprParser parser (getErrorHandler(), getContext(), mLocals, mLiterals);
+        
+        for (std::string::const_iterator iter (arguments.begin()); iter!=arguments.end();
+            ++iter)
+        {
+            parser.reset();    
+            scanner.scan (parser);
+
+            char type = parser.append (mCode);
+
+            if (type!=*iter)
+                Generator::convert (mCode, type, *iter);
+                
+            mOperands.push_back (*iter);
+        }
+    }
+            
     ExprParser::ExprParser (ErrorHandler& errorHandler, Context& context, Locals& locals,
         Literals& literals)
     : Parser (errorHandler, context), mLocals (locals), mLiterals (literals),
@@ -193,6 +212,17 @@ namespace Compiler
 
     bool ExprParser::parseKeyword (int keyword, const TokenLoc& loc, Scanner& scanner)
     {
+        if (keyword==Scanner::K_getsquareroot && mNextOperand)
+        {
+            mTokenLoc = loc;        
+            parseArguments ("f", scanner);
+
+            Generator::squareRoot (mCode);
+            
+            mNextOperand = false;
+            return true;
+        }
+        
         return Parser::parseKeyword (keyword, loc, scanner);
     }
 
@@ -234,14 +264,17 @@ namespace Compiler
             return true;
         }
         
-        mTokenLoc = loc;
-   
-        switch (code)
+        if (!mNextOperand)
         {
-            case Scanner::S_plus: pushBinaryOperator ('+'); return true;
-            case Scanner::S_minus: pushBinaryOperator ('-'); return true;
-            case Scanner::S_mult: pushBinaryOperator ('*'); return true;
-            case Scanner::S_div: pushBinaryOperator ('/'); return true;
+            mTokenLoc = loc;
+   
+            switch (code)
+            {
+                case Scanner::S_plus: pushBinaryOperator ('+'); return true;
+                case Scanner::S_minus: pushBinaryOperator ('-'); return true;
+                case Scanner::S_mult: pushBinaryOperator ('*'); return true;
+                case Scanner::S_div: pushBinaryOperator ('/'); return true;
+            }
         }
         
         return Parser::parseSpecial (code, loc, scanner);
diff --git a/components/compiler/exprparser.hpp b/components/compiler/exprparser.hpp
index a87dd995b..6dba519ea 100644
--- a/components/compiler/exprparser.hpp
+++ b/components/compiler/exprparser.hpp
@@ -44,6 +44,8 @@ namespace Compiler
             void pushBinaryOperator (char c);
                         
             void close();
+            
+            void parseArguments (const std::string& arguments, Scanner& scanner);
                         
         public:
     
diff --git a/components/compiler/generator.cpp b/components/compiler/generator.cpp
index 971fd81b3..e704ac724 100644
--- a/components/compiler/generator.cpp
+++ b/components/compiler/generator.cpp
@@ -4,6 +4,7 @@
 #include <cassert>
 #include <algorithm>
 #include <iterator>
+#include <stdexcept>
 
 #include "literals.hpp"
 
@@ -144,6 +145,11 @@ namespace
     {
         code.push_back (segment5 (18));
     }    
+
+    void opSquareRoot (Compiler::Generator::CodeContainer& code)
+    {
+        code.push_back (segment5 (19));
+    }    
 }
 
 namespace Compiler
@@ -297,6 +303,24 @@ namespace Compiler
                 opDivFloat (code);
             }        
         }
+        
+        void convert (CodeContainer& code, char fromType, char toType)
+        {
+            if (fromType!=toType)
+            {
+                if (fromType=='f' && toType=='l')
+                    opFloatToInt (code);
+                else if (fromType=='l' && toType=='f')
+                    opIntToFloat (code);
+                else
+                    throw std::logic_error ("illegal type conversion");
+            }
+        }
+        
+        void squareRoot (CodeContainer& code)
+        {
+            opSquareRoot (code);
+        }
     }
 }
 
diff --git a/components/compiler/generator.hpp b/components/compiler/generator.hpp
index cea8a8636..44b0fc4f2 100644
--- a/components/compiler/generator.hpp
+++ b/components/compiler/generator.hpp
@@ -29,6 +29,10 @@ namespace Compiler
         void mul (CodeContainer& code, char valueType1, char valueType2);        
         
         void div (CodeContainer& code, char valueType1, char valueType2);        
+        
+        void convert (CodeContainer& code, char fromType, char toType);
+        
+        void squareRoot (CodeContainer& code);
     }
 }
 
diff --git a/components/compiler/scanner.cpp b/components/compiler/scanner.cpp
index 17b2dc305..e04e2114b 100644
--- a/components/compiler/scanner.cpp
+++ b/components/compiler/scanner.cpp
@@ -213,6 +213,7 @@ namespace Compiler
             "return",
             "messagebox",
             "set", "to",
+            "getsquareroot",
             0
         };
 
diff --git a/components/compiler/scanner.hpp b/components/compiler/scanner.hpp
index 63a0dbb4d..5a490d70e 100644
--- a/components/compiler/scanner.hpp
+++ b/components/compiler/scanner.hpp
@@ -35,7 +35,8 @@ namespace Compiler
                 K_while, K_endwhile,
                 K_return,
                 K_messageBox,
-                K_set, K_to
+                K_set, K_to,
+                K_getsquareroot
             };
 
             enum special
diff --git a/components/interpreter/docs/vmformat.txt b/components/interpreter/docs/vmformat.txt
index db85e6af8..748e6e3ee 100644
--- a/components/interpreter/docs/vmformat.txt
+++ b/components/interpreter/docs/vmformat.txt
@@ -70,6 +70,7 @@ op  15: div (integer) stack[1] by stack[0], pop twice, push result
 op  16: div (float) stack[1] by stack[0], pop twice, push result
 op  17: convert stack[1] from integer to float
 op  18: convert stack[1] from float to integer
-opcodes 19-33554431 unused
+op  19: take square root of stack[0] (float)
+opcodes 20-33554431 unused
 opcodes 33554432-67108863 reserved for extensions
 
diff --git a/components/interpreter/installopcodes.cpp b/components/interpreter/installopcodes.cpp
index a0f90b98e..b96a0a1a5 100644
--- a/components/interpreter/installopcodes.cpp
+++ b/components/interpreter/installopcodes.cpp
@@ -35,6 +35,7 @@ namespace Interpreter
         interpreter.installSegment5 (14, new OpMulInt<Type_Float>);
         interpreter.installSegment5 (15, new OpDivInt<Type_Integer>);
         interpreter.installSegment5 (16, new OpDivInt<Type_Float>);
+        interpreter.installSegment5 (19, new OpSquareRoot);        
     }
 }
 
diff --git a/components/interpreter/mathopcodes.hpp b/components/interpreter/mathopcodes.hpp
index 4cec3bfc9..bb12274d3 100644
--- a/components/interpreter/mathopcodes.hpp
+++ b/components/interpreter/mathopcodes.hpp
@@ -2,6 +2,7 @@
 #define INTERPRETER_MATHOPCODES_H_INCLUDED
 
 #include <stdexcept>
+#include <cmath>
 
 #include "opcodes.hpp"
 #include "runtime.hpp"
@@ -84,6 +85,24 @@ namespace Interpreter
                 runtime[0] = *reinterpret_cast<Type_Data *> (&result);
             }           
     };
+    
+    class OpSquareRoot : public Opcode0
+    {
+        public:
+        
+            virtual void execute (Runtime& runtime)
+            {
+                Type_Float value = *reinterpret_cast<Type_Float *> (&runtime[0]);
+                
+                if (value<0)
+                    throw std::runtime_error (
+                        "square root of negative number (we aren't that imaginary)");
+                
+                value = std::sqrt (value);
+                
+                runtime[0] = *reinterpret_cast<Type_Data *> (&value);
+            }           
+    };    
 }
 
 #endif