diff --git a/doc/classes.texi b/doc/classes.texi
index 4573b5a..9dc4e10 100644
--- a/doc/classes.texi
+++ b/doc/classes.texi
@@ -1308,6 +1308,9 @@ The subtype must implement at least the number of arguments declared in
 @var{args}, but the names needn't match.
   @itemize
   @item
+  Each name in @var{args} must be a valid variable name, as satisfied by the
+  regular expression @code{/^[a-z][a-z0-9]*$/i}.
+  @item
   The names are use purely for documentation and are not semantic.
   @end itemize
 @end itemize
diff --git a/lib/interface.js b/lib/interface.js
index 0f2b6ae..35efa7d 100644
--- a/lib/interface.js
+++ b/lib/interface.js
@@ -235,6 +235,23 @@ var extend = ( function( extending )
                         );
                     }
 
+                    var dfn = value.definition,
+                        i   = dfn.length;
+
+                    // only permit valid names for argument list (in the future,
+                    // we may add additional functionality, so it's important to
+                    // restrict this as much as possible for the time being)
+                    while ( i-- )
+                    {
+                        if ( dfn[ i ].match( /^[a-z][a-z0-9]*$/i ) === null )
+                        {
+                            throw SyntaxError(
+                                iname + " member " + name +
+                                " contains invalid argument: '" + name + "'"
+                            );
+                        }
+                    }
+
                     member_builder.buildMethod(
                         members, null, name, value, keywords
                     );
diff --git a/test/test-interface-name.js b/test/test-interface-name.js
index ba1bd09..5a21efe 100644
--- a/test/test-interface-name.js
+++ b/test/test-interface-name.js
@@ -243,3 +243,27 @@ var common     = require( './common' ),
     }
 } )();
 
+
+/**
+ * At this point in time, we are unsure what we will allow within interface
+ * definitions in the future (e.g. possible type hinting). As such, we will
+ * simply allow only valid variable names for now (like a function definition).
+ */
+( function testTriggersErrorIfInvalidVarNamesAreUsedAsArgumentNames()
+{
+    assert['throws']( function()
+    {
+        Interface( { foo: [ 'invalid name' ] } );
+    }, SyntaxError, 'Only var names should be permitted in interface dfns' );
+
+    assert['throws']( function()
+    {
+        Interface( { foo: [ '1invalid' ] } );
+    }, SyntaxError, 'Only var names should be permitted in interface dfns: 2' );
+
+    assert.doesNotThrow( function()
+    {
+        Interface( { foo: [ 'valid' ] } );
+    }, SyntaxError, 'Valid var names as args should not throw exceptions' );
+} )();
+