diff --git a/cc_macro.c b/cc_macro.c
index 35a1598..81a4a38 100644
--- a/cc_macro.c
+++ b/cc_macro.c
@@ -33,6 +33,7 @@ struct macro_list
 {
 	struct macro_list* next;
 	char* symbol;
+	struct token_list* expansion;
 };
 
 struct macro_list* macro_env;
@@ -72,6 +73,44 @@ void eat_newline_tokens()
 	}
 }
 
+/* returns the first token inserted; inserts *before* point */
+struct token_list* insert_tokens(struct token_list* point, struct token_list* token)
+{
+	struct token_list* copy;
+	struct token_list* first = NULL;
+
+	while (NULL != token)
+	{
+		copy = calloc(1, sizeof(struct token_list));
+		copy->s = token->s;
+		copy->filename = token->filename;
+		copy->linenumber = token->linenumber;
+
+		if(NULL == first)
+		{
+			first = copy;
+		}
+
+		copy->next = point;
+
+		if (NULL != point)
+		{
+			copy->prev = point->prev;
+
+			if(NULL != point->prev)
+			{
+				point->prev->next = copy;
+			}
+
+			point->prev = copy;
+		}
+
+		token = token->next;
+	}
+
+	return first;
+}
+
 struct macro_list* lookup_macro(struct token_list* token)
 {
 	struct macro_list* hold = macro_env;
@@ -307,18 +346,10 @@ int macro_expression()
 
 void handle_define()
 {
-	int replace_with_constant = TRUE;
 	struct macro_list* hold;
+	struct token_list* expansion_end;
 
-	if (replace_with_constant)
-	{
-		macro_token->s = "CONSTANT";
-		macro_token = macro_token->next;
-	}
-	else
-	{
-		eat_current_token();
-	}
+	eat_current_token();
 
 	require(NULL != macro_token, "got an EOF terminated #define\n");
 	require('\n' != macro_token->s[0], "unexpected newline after #define\n");
@@ -329,24 +360,31 @@ void handle_define()
 	hold->next = macro_env;
 	macro_env = hold;
 
+	/* discard the macro name */
+	eat_current_token();
+
 	while (TRUE)
 	{
 		require(NULL != macro_token, "got an EOF terminated #define\n");
 
 		if ('\n' == macro_token->s[0])
 		{
+			expansion_end->next = NULL;
 			return;
 		}
 
-		if (replace_with_constant)
+		expansion_end = macro_token;
+
+		/* in the first iteration, we set the first token of the expansion, if
+		   it exists */
+		if (NULL == hold->expansion)
 		{
-			macro_token = macro_token->next;
-		}
-		else
-		{
-			eat_current_token();
+			hold->expansion = macro_token;
 		}
+
+		eat_current_token();
 	}
+
 }
 
 void macro_directive()
@@ -427,6 +465,21 @@ void macro_directive()
 	}
 }
 
+struct token_list* maybe_expand(struct token_list* token)
+{
+	struct macro_list* hold = lookup_macro(token);
+	struct token_list* hold2;
+	if (NULL == hold)
+	{
+		return token->next;
+	}
+
+	token = eat_token(token);
+	hold2 = insert_tokens(token, hold->expansion);
+
+	return hold2->next;
+}
+
 void preprocess()
 {
 	int start_of_line = TRUE;
@@ -459,10 +512,9 @@ void preprocess()
 		else
 		{
 			start_of_line = FALSE;
-
 			if(NULL == conditional_inclusion_top)
 			{
-				macro_token = macro_token->next;
+				macro_token = maybe_expand(macro_token);
 			}
 			else if(!conditional_inclusion_top->include)
 			{
@@ -471,7 +523,7 @@ void preprocess()
 			}
 			else
 			{
-				macro_token = macro_token->next;
+				macro_token = maybe_expand(macro_token);
 			}
 		}
 	}
diff --git a/test/test.answers b/test/test.answers
index 3a2152c..8864270 100644
--- a/test/test.answers
+++ b/test/test.answers
@@ -175,8 +175,8 @@ a2a83f42119e646b389b98647cf6cf2aa9597185997c9453db746178c8c4c0bf  test/results/t
 698853b79efb30865a663c4863c050639eb21c7400008f7840830503928973d4  test/results/test0106-knight-native-binary
 45c2ba61dc209d7ffa39de9ff0f0a7f8f3ea4d7e38598c72f982fcaf9a05c84a  test/results/test0106-knight-posix-binary
 944580ff4aae38aafac139faf6eed5bfe4ff68b01a7a3adfa346de8803101182  test/results/test0106-x86-binary
-d4ea011b32eabe55d30d9872fb62472a7941845cf2c9198bd84378fce9098505  test/results/test1000-aarch64-binary
-0c21df6c75998ef0d2e4188e591759b147d1d3011675c2243b9d5d90f93745c9  test/results/test1000-amd64-binary
-b97927188f7683005fb97d82f88a232284a7b472446f4afb2c5ccdef59f335f8  test/results/test1000-armv7l-binary
-d67c1c38a4d3e8b4461df71754a7d0ae556e549a7718fd190964e0a3c1835ecf  test/results/test1000-knight-posix-binary
-42dd021d8a0c8979a8796b1f459f29adca28b293b73530d17f34753b5a17d016  test/results/test1000-x86-binary
+26e9a6dd65d2cd9f7ad45b0dc145239b9317c77029c6b69faf922a9af65a0678  test/results/test1000-aarch64-binary
+421f97cb2c0ea0fbdc6ac366a340657682bf1ed9f36f7edad9972f61eb9ec2a8  test/results/test1000-amd64-binary
+7486674615d8165e5e0365070a1e20142c12d334db7393fbeafa46d14c5c74c5  test/results/test1000-armv7l-binary
+8e7f3f18441a8f5762741f1362d6789098fbb8c9f7ac722b7036416e7e602b25  test/results/test1000-knight-posix-binary
+02f26abda516b431ea6e01cfd135e45cd387fa71470495aba005bc121e23c425  test/results/test1000-x86-binary
diff --git a/test/test1000/proof.answer b/test/test1000/proof.answer
index 1d5860b..cdc7f22 100644
--- a/test/test1000/proof.answer
+++ b/test/test1000/proof.answer
@@ -1 +1 @@
-5717733f915e9c4251f773783e210ca4b25e6a3c2f78c182fd905209911c974e  test/test1000/proof
+61dde3b8a913296de7da40208428ff28ff741908ea9e98c7856626b19666288f  test/test1000/proof