diff --git a/Sources/parser.c b/Sources/parser.c
index 3873900..8793cb0 100644
--- a/Sources/parser.c
+++ b/Sources/parser.c
@@ -379,7 +379,7 @@ static expression *parse_assign(state_t *state) {
 	while (!done) {
 		if (current(state).kind == TOKEN_OPERATOR) {
 			operatorr op = current(state).op;
-			if (op == OPERATOR_ASSIGN) {
+			if (op == OPERATOR_ASSIGN || op == OPERATOR_MINUS_ASSIGN || op == OPERATOR_PLUS_ASSIGN || op == OPERATOR_DIVIDE_ASSIGN || op == OPERATOR_MULTIPLY_ASSIGN) {
 				advance_state(state);
 				expression *right = parse_logical(state);
 				expression *expression = expression_allocate();
diff --git a/Sources/tokenizer.c b/Sources/tokenizer.c
index f36be77..4abbe96 100644
--- a/Sources/tokenizer.c
+++ b/Sources/tokenizer.c
@@ -453,6 +453,26 @@ tokens tokenize(const char *filename, const char *source) {
 					token.op = OPERATOR_MOD;
 					tokens_add(&tokens, token);
 				}
+				else if (tokenizer_buffer_equals(&buffer, "-=")) {
+					token token = token_create(TOKEN_OPERATOR, &state);
+					token.op = OPERATOR_MINUS_ASSIGN;
+					tokens_add(&tokens, token);
+				}
+				else if (tokenizer_buffer_equals(&buffer, "+=")) {
+					token token = token_create(TOKEN_OPERATOR, &state);
+					token.op = OPERATOR_PLUS_ASSIGN;
+					tokens_add(&tokens, token);
+				}
+				else if (tokenizer_buffer_equals(&buffer, "/=")) {
+					token token = token_create(TOKEN_OPERATOR, &state);
+					token.op = OPERATOR_DIVIDE_ASSIGN;
+					tokens_add(&tokens, token);
+				}
+				else if (tokenizer_buffer_equals(&buffer, "*=")) {
+					token token = token_create(TOKEN_OPERATOR, &state);
+					token.op = OPERATOR_MULTIPLY_ASSIGN;
+					tokens_add(&tokens, token);
+				}
 				else if (tokenizer_buffer_equals(&buffer, "=")) {
 					token token = token_create(TOKEN_OPERATOR, &state);
 					token.op = OPERATOR_ASSIGN;
diff --git a/Sources/tokenizer.h b/Sources/tokenizer.h
index 5bb1ee3..c2e4db2 100644
--- a/Sources/tokenizer.h
+++ b/Sources/tokenizer.h
@@ -20,7 +20,11 @@ typedef enum operatorr {
 	OPERATOR_OR,
 	OPERATOR_AND,
 	OPERATOR_MOD,
-	OPERATOR_ASSIGN
+	OPERATOR_ASSIGN,
+	OPERATOR_MINUS_ASSIGN,
+	OPERATOR_PLUS_ASSIGN,
+	OPERATOR_DIVIDE_ASSIGN,
+	OPERATOR_MULTIPLY_ASSIGN
 } operatorr;
 
 typedef struct token {