diff --git a/src/sixtypical/analyzer.py b/src/sixtypical/analyzer.py
index ecb3b57..11c21ff 100644
--- a/src/sixtypical/analyzer.py
+++ b/src/sixtypical/analyzer.py
@@ -372,23 +372,23 @@ class Analyzer(object):
         context = Context(self.routines, routine, type_.inputs, type_.outputs, type_.trashes)
 
         if self.debug:
-            print "at start of routine `{}`:".format(routine.name)
-            print context
+            print("at start of routine `{}`:".format(routine.name))
+            print(context)
 
         self.analyze_block(routine.block, context)
         trashed = set(context.each_touched()) - set(context.each_meaningful())
 
         if self.debug:
-            print "at end of routine `{}`:".format(routine.name)
-            print context
-            print "trashed: ", LocationRef.format_set(trashed)
-            print "outputs: ", LocationRef.format_set(type_.outputs)
+            print("at end of routine `{}`:".format(routine.name))
+            print(context)
+            print("trashed: ", LocationRef.format_set(trashed))
+            print("outputs: ", LocationRef.format_set(type_.outputs))
             trashed_outputs = type_.outputs & trashed
             if trashed_outputs:
-                print "TRASHED OUTPUTS: ", LocationRef.format_set(trashed_outputs)
-            print ''
-            print '-' * 79
-            print ''
+                print("TRASHED OUTPUTS: ", LocationRef.format_set(trashed_outputs))
+            print('')
+            print('-' * 79)
+            print('')
 
         # even if we goto another routine, we can't trash an output.
         for ref in trashed:
diff --git a/src/sixtypical/compiler.py b/src/sixtypical/compiler.py
index 34ed70f..be610b8 100644
--- a/src/sixtypical/compiler.py
+++ b/src/sixtypical/compiler.py
@@ -112,7 +112,7 @@ class Compiler(object):
             routine_name = roster_row[-1]
             self.compile_routine(self.routines[routine_name])
 
-        for location, label in self.trampolines.iteritems():
+        for location, label in self.trampolines.items():
             self.emitter.resolve_label(label)
             self.emitter.emit(JMP(Indirect(self.get_label(location.name))))
             self.emitter.emit(RTS())
diff --git a/src/sixtypical/emitter.py b/src/sixtypical/emitter.py
index a1b962c..6ea308a 100644
--- a/src/sixtypical/emitter.py
+++ b/src/sixtypical/emitter.py
@@ -13,7 +13,7 @@ class Emittable(object):
 
 class Byte(Emittable):
     def __init__(self, value):
-        if isinstance(value, basestring):
+        if isinstance(value, str):
             value = ord(value)
         if value < -127 or value > 255:
             raise IndexError(value)
diff --git a/src/sixtypical/model.py b/src/sixtypical/model.py
index 30d5d54..6effc49 100644
--- a/src/sixtypical/model.py
+++ b/src/sixtypical/model.py
@@ -20,7 +20,7 @@ class Type(object):
 
     def backpatch_constraint_labels(self, resolver):
         def resolve(w):
-             if not isinstance(w, basestring):
+             if not isinstance(w, str):
                  return w
              return resolver(w)
         if isinstance(self, TableType):
diff --git a/src/sixtypical/parser.py b/src/sixtypical/parser.py
index e16cf66..8cee87a 100644
--- a/src/sixtypical/parser.py
+++ b/src/sixtypical/parser.py
@@ -90,7 +90,7 @@ class Parser(object):
         self.scanner.check_type('EOF')
 
         # now backpatch the executable types.
-        #for type_name, type_ in self.context.typedefs.iteritems():
+        #for type_name, type_ in self.context.typedefs.items():
         #    type_.backpatch_constraint_labels(lambda w: self.lookup(w))
         for defn in defns:
             defn.location.type.backpatch_constraint_labels(lambda w: self.lookup(w))
@@ -103,7 +103,7 @@ class Parser(object):
                 if not isinstance(model.type, (RoutineType, VectorType)):
                     self.syntax_error('Illegal call of non-executable "%s"' % name)
                 instr.location = model
-            if instr.opcode in ('copy',) and isinstance(instr.src, basestring):
+            if instr.opcode in ('copy',) and isinstance(instr.src, str):
                 name = instr.src
                 model = self.lookup(name)
                 if not isinstance(model.type, (RoutineType, VectorType)):
@@ -359,7 +359,7 @@ class Parser(object):
 
     def indexed_locexpr(self, forward=False):
         loc = self.locexpr(forward=forward)
-        if not isinstance(loc, basestring):
+        if not isinstance(loc, str):
             index = None
             if self.scanner.consume('+'):
                 index = self.locexpr()