diff --git a/src/battle/bullets.c b/src/battle/bullets.c
index 6ce80ed..e0982f6 100644
--- a/src/battle/bullets.c
+++ b/src/battle/bullets.c
@@ -56,7 +56,7 @@ void initBulletDefs(void)
 		def->damage = cJSON_GetObjectItem(node, "damage")->valueint;
 		def->texture = getTexture(cJSON_GetObjectItem(node, "textureName")->valuestring);
 		def->sound = lookup(cJSON_GetObjectItem(node, "sound")->valuestring);
-		def->flags = flagsToLong(cJSON_GetObjectItem(node, "flags")->valuestring);
+		def->flags = flagsToLong(cJSON_GetObjectItem(node, "flags")->valuestring, NULL);
 		
 		SDL_QueryTexture(def->texture, NULL, NULL, &def->w, &def->h);
 	}
diff --git a/src/battle/bullets.h b/src/battle/bullets.h
index f88940f..f42cf9e 100644
--- a/src/battle/bullets.h
+++ b/src/battle/bullets.h
@@ -31,7 +31,7 @@ extern void blitRotated(SDL_Texture *texture, int x, int y, int angle);
 extern int collision(int x1, int y1, int w1, int h1, int x2, int y2, int w2, int h2);
 extern void damageFighter(Entity *f, int damage, long flags);
 extern void playBattleSound(int id, int x, int y);
-extern long flagsToLong(char *flags);
+extern long flagsToLong(char *flags, int *add);
 extern long lookup(char *name);
 extern char *readFile(char *filename);
 extern float getAngle(int x1, int y1, int x2, int y2);
diff --git a/src/battle/capitalShips.c b/src/battle/capitalShips.c
index 20ab112..f174a37 100644
--- a/src/battle/capitalShips.c
+++ b/src/battle/capitalShips.c
@@ -363,14 +363,14 @@ static void loadComponents(Entity *parent, cJSON *components)
 			
 			SDL_QueryTexture(e->texture, NULL, NULL, &e->w, &e->h);
 			
-			if (cJSON_GetObjectItem(component, "aiFlags"))
-			{
-				e->aiFlags = flagsToLong(cJSON_GetObjectItem(component, "aiFlags")->valuestring);
-			}
-			
 			if (cJSON_GetObjectItem(component, "flags"))
 			{
-				e->flags = flagsToLong(cJSON_GetObjectItem(component, "flags")->valuestring);
+				e->flags = flagsToLong(cJSON_GetObjectItem(component, "flags")->valuestring, NULL);
+			}
+			
+			if (cJSON_GetObjectItem(component, "aiFlags"))
+			{
+				e->aiFlags = flagsToLong(cJSON_GetObjectItem(component, "aiFlags")->valuestring, NULL);
 			}
 			
 			e->systemPower = 100;
@@ -419,14 +419,14 @@ static void loadGuns(Entity *parent, cJSON *guns)
 				e->missiles = cJSON_GetObjectItem(gun, "missiles")->valueint;
 			}
 			
-			if (cJSON_GetObjectItem(gun, "aiFlags"))
-			{
-				e->aiFlags = flagsToLong(cJSON_GetObjectItem(gun, "aiFlags")->valuestring);
-			}
-			
 			if (cJSON_GetObjectItem(gun, "flags"))
 			{
-				e->flags = flagsToLong(cJSON_GetObjectItem(gun, "flags")->valuestring);
+				e->flags = flagsToLong(cJSON_GetObjectItem(gun, "flags")->valuestring, NULL);
+			}
+			
+			if (cJSON_GetObjectItem(gun, "aiFlags"))
+			{
+				e->aiFlags = flagsToLong(cJSON_GetObjectItem(gun, "aiFlags")->valuestring, NULL);
 			}
 			
 			SDL_QueryTexture(e->texture, NULL, NULL, &e->w, &e->h);
@@ -471,7 +471,7 @@ static void loadEngines(Entity *parent, cJSON *engines)
 			
 			if (cJSON_GetObjectItem(engine, "flags"))
 			{
-				e->flags = flagsToLong(cJSON_GetObjectItem(engine, "flags")->valuestring);
+				e->flags = flagsToLong(cJSON_GetObjectItem(engine, "flags")->valuestring, NULL);
 			}
 			
 			SDL_QueryTexture(e->texture, NULL, NULL, &e->w, &e->h);
diff --git a/src/battle/capitalShips.h b/src/battle/capitalShips.h
index edab4c5..a16ef54 100644
--- a/src/battle/capitalShips.h
+++ b/src/battle/capitalShips.h
@@ -32,7 +32,7 @@ extern float getAngle(int x1, int y1, int x2, int y2);
 extern SDL_Texture *getTexture(char *filename);
 extern char *readFile(char *filename);
 extern char *getFileLocation(char *filename);
-extern long flagsToLong(char *flags);
+extern long flagsToLong(char *flags, int *add);
 extern long lookup(char *name);
 extern void doAI(void);
 extern float getAngle(int x1, int y1, int x2, int y2);
diff --git a/src/battle/fighters.c b/src/battle/fighters.c
index 64720fc..e33818c 100644
--- a/src/battle/fighters.c
+++ b/src/battle/fighters.c
@@ -649,12 +649,12 @@ static void loadFighterDef(char *filename)
 	
 	if (cJSON_GetObjectItem(root, "flags"))
 	{
-		f->flags = flagsToLong(cJSON_GetObjectItem(root, "flags")->valuestring);
+		f->flags = flagsToLong(cJSON_GetObjectItem(root, "flags")->valuestring, NULL);
 	}
 	
 	if (cJSON_GetObjectItem(root, "aiFlags"))
 	{
-		f->aiFlags = flagsToLong(cJSON_GetObjectItem(root, "aiFlags")->valuestring);
+		f->aiFlags = flagsToLong(cJSON_GetObjectItem(root, "aiFlags")->valuestring, NULL);
 	}
 	
 	f->separationRadius = MAX(f->w, f->h);
diff --git a/src/battle/fighters.h b/src/battle/fighters.h
index 9579e24..30608d8 100644
--- a/src/battle/fighters.h
+++ b/src/battle/fighters.h
@@ -39,7 +39,7 @@ extern void adjustObjectiveTargetValue(char *name, int type, int amount);
 extern void attachRope(void);
 extern char *readFile(char *filename);
 extern long lookup(char *name);
-extern long flagsToLong(char *flags);
+extern long flagsToLong(char *flags, int *add);
 extern void addShieldSplinterEffect(Entity *ent);
 extern void completeMission(void);
 extern void runScriptFunction(char *format, ...);
diff --git a/src/galaxy/mission.c b/src/galaxy/mission.c
index cfeaa45..787d145 100644
--- a/src/galaxy/mission.c
+++ b/src/galaxy/mission.c
@@ -201,7 +201,7 @@ static void loadFighters(cJSON *node)
 	Entity *f;
 	char **types, *name, *groupName, *type;
 	int side, scatter, number, active;
-	int i, numTypes;
+	int i, numTypes, addFlags, addAIFlags;
 	long flags, aiFlags;
 	float x, y;
 	
@@ -251,12 +251,12 @@ static void loadFighters(cJSON *node)
 			
 			if (cJSON_GetObjectItem(node, "flags"))
 			{
-				flags = flagsToLong(cJSON_GetObjectItem(node, "flags")->valuestring);
+				flags = flagsToLong(cJSON_GetObjectItem(node, "flags")->valuestring, &addFlags);
 			}
 			
 			if (cJSON_GetObjectItem(node, "aiFlags"))
 			{
-				aiFlags = flagsToLong(cJSON_GetObjectItem(node, "aiFlags")->valuestring);
+				aiFlags = flagsToLong(cJSON_GetObjectItem(node, "aiFlags")->valuestring, &addAIFlags);
 			}
 			
 			for (i = 0 ; i < number ; i++)
@@ -275,12 +275,30 @@ static void loadFighters(cJSON *node)
 				
 				if (flags != -1)
 				{
-					f->flags = flags;
+					if (addFlags)
+					{
+						f->flags |= flags;
+					}
+					else
+					{
+						f->flags = flags;
+						
+						SDL_LogMessage(SDL_LOG_CATEGORY_APPLICATION, SDL_LOG_PRIORITY_WARN, "Flags for '%s' (%s) replaced", f->name, f->defName);
+					}
 				}
 				
 				if (aiFlags != -1)
 				{
-					f->aiFlags = aiFlags;
+					if (addAIFlags)
+					{
+						f->aiFlags |= aiFlags;
+					}
+					else
+					{
+						f->aiFlags = aiFlags;
+						
+						SDL_LogMessage(SDL_LOG_CATEGORY_APPLICATION, SDL_LOG_PRIORITY_WARN, "AI Flags for '%s' (%s) replaced", f->name, f->defName);
+					}
 				}
 				
 				if (name)
@@ -306,7 +324,7 @@ static void loadCapitalShips(cJSON *node)
 	Entity *e;
 	char **types, *name, *groupName, *type;
 	int side, scatter, number, active;
-	int i, numTypes;
+	int i, numTypes, addFlags;
 	long flags;
 	float x, y;
 	
@@ -355,7 +373,7 @@ static void loadCapitalShips(cJSON *node)
 			
 			if (cJSON_GetObjectItem(node, "flags"))
 			{
-				flags = flagsToLong(cJSON_GetObjectItem(node, "flags")->valuestring);
+				flags = flagsToLong(cJSON_GetObjectItem(node, "flags")->valuestring, &addFlags);
 			}
 			
 			for (i = 0 ; i < number ; i++)
@@ -384,7 +402,16 @@ static void loadCapitalShips(cJSON *node)
 				
 				if (flags != -1)
 				{
-					e->flags = flags;
+					if (addFlags)
+					{
+						e->flags |= flags;
+					}
+					else
+					{
+						e->flags = flags;
+						
+						SDL_LogMessage(SDL_LOG_CATEGORY_APPLICATION, SDL_LOG_PRIORITY_WARN, "Flags for '%s' (%s) replaced", e->name, e->defName);
+					}
 				}
 			}
 		
@@ -494,7 +521,7 @@ static void loadItems(cJSON *node)
 {
 	Entity *e;
 	char *name, *groupName, *type;
-	int i, scatter, number, active;
+	int i, scatter, number, active, addFlags;
 	long flags;
 	float x, y;
 	
@@ -537,7 +564,7 @@ static void loadItems(cJSON *node)
 			
 			if (cJSON_GetObjectItem(node, "flags"))
 			{
-				flags = flagsToLong(cJSON_GetObjectItem(node, "flags")->valuestring);
+				flags = flagsToLong(cJSON_GetObjectItem(node, "flags")->valuestring, &addFlags);
 			}
 			
 			if (cJSON_GetObjectItem(node, "active"))
@@ -561,7 +588,16 @@ static void loadItems(cJSON *node)
 				
 				if (flags != -1)
 				{
-					e->flags = flags;
+					if (addFlags)
+					{
+						e->flags |= flags;
+					}
+					else
+					{
+						e->flags = flags;
+						
+						SDL_LogMessage(SDL_LOG_CATEGORY_APPLICATION, SDL_LOG_PRIORITY_WARN, "Flags for '%s' (%s) replaced", e->name, e->defName);
+					}
 				}
 				
 				e->x = x;
diff --git a/src/galaxy/mission.h b/src/galaxy/mission.h
index 2667899..55ec80d 100644
--- a/src/galaxy/mission.h
+++ b/src/galaxy/mission.h
@@ -34,7 +34,7 @@ extern void endSectionTransition(void);
 extern void playMusic(char *filename);
 extern void stopMusic(void);
 extern void initPlayer(void);
-extern long flagsToLong(char *flags);
+extern long flagsToLong(char *flags, int *add);
 extern Entity *spawnWaypoint(void);
 extern void activateNextWaypoint(void);
 extern void selectWidget(const char *name, const char *group);
diff --git a/src/system/lookup.c b/src/system/lookup.c
index e304415..9998d58 100644
--- a/src/system/lookup.c
+++ b/src/system/lookup.c
@@ -215,13 +215,18 @@ char *getFlagValues(char *prefix, long flags)
 	return flagStr;
 }
 
-long flagsToLong(char *flags)
+long flagsToLong(char *flags, int *add)
 {
 	char *flag;
 	long total;
 	
 	total = 0;
 	
+	if (add)
+	{
+		*add = (flags[0] == '+');
+	}
+	
 	flag = strtok(flags, "+");
 	while (flag)
 	{