diff --git a/Quake/common.c b/Quake/common.c
index 71ef7624..96c01eb9 100644
--- a/Quake/common.c
+++ b/Quake/common.c
@@ -1453,7 +1453,7 @@ void COM_WriteFile (const char *filename, const void *data, int len)
 
 	Sys_mkdir (com_gamedir); //johnfitz -- if we've switched to a nonexistant gamedir, create it now so we don't crash
 
-	sprintf (name, "%s/%s", com_gamedir, filename);
+	q_snprintf (name, sizeof(name), "%s/%s", com_gamedir, filename);
 
 	handle = Sys_FileOpenWrite (name);
 	if (handle == -1)
@@ -1572,7 +1572,7 @@ static int COM_FindFile (const char *filename, int *handle, FILE **file,
 					continue;
 			}
 
-			sprintf (netpath, "%s/%s",search->filename, filename);
+			q_snprintf (netpath, sizeof(netpath), "%s/%s",search->filename, filename);
 			findtime = Sys_FileTime (netpath);
 			if (findtime == -1)
 				continue;
@@ -1887,7 +1887,7 @@ void COM_AddGameDirectory (const char *dir)
 	// add any pak files in the format pak0.pak pak1.pak, ...
 	for (i = 0; ; i++)
 	{
-		sprintf (pakfile, "%s/pak%i.pak", dir, i);
+		q_snprintf (pakfile, sizeof(pakfile), "%s/pak%i.pak", dir, i);
 		pak = COM_LoadPackFile (pakfile);
 		if (!pak)
 			break;
diff --git a/Quake/console.c b/Quake/console.c
index d1f220a1..b4b62934 100644
--- a/Quake/console.c
+++ b/Quake/console.c
@@ -162,7 +162,7 @@ void Con_Dump_f (void)
 #if 1
 	//johnfitz -- there is a security risk in writing files with an arbitrary filename. so,
 	//until stuffcmd is crippled to alleviate this risk, just force the default filename.
-	sprintf (name, "%s/condump.txt", com_gamedir);
+	q_snprintf (name, sizeof(name), "%s/condump.txt", com_gamedir);
 #else
 	if (Cmd_Argc() > 2)
 	{
@@ -177,11 +177,11 @@ void Con_Dump_f (void)
 			Con_Printf ("Relative pathnames are not allowed.\n");
 			return;
 		}
-		sprintf (name, "%s/%s", com_gamedir, Cmd_Argv(1));
+		q_snprintf (name, sizeof(name), "%s/%s", com_gamedir, Cmd_Argv(1));
 		COM_DefaultExtension (name, ".txt", sizeof(name));
 	}
 	else
-		sprintf (name, "%s/condump.txt", com_gamedir);
+		q_snprintf (name, sizeof(name), "%s/condump.txt", com_gamedir);
 #endif
 
 	COM_CreatePath (name);
diff --git a/Quake/gl_draw.c b/Quake/gl_draw.c
index a1c9937c..2d4ce312 100644
--- a/Quake/gl_draw.c
+++ b/Quake/gl_draw.c
@@ -246,7 +246,7 @@ qpic_t *Draw_PicFromWad (const char *name)
 	else
 	{
 		char texturename[64]; //johnfitz
-		sprintf (texturename, "%s:%s", WADFILENAME, name); //johnfitz
+		q_snprintf (texturename, sizeof(texturename), "%s:%s", WADFILENAME, name); //johnfitz
 
 		offset = (src_offset_t)p - (src_offset_t)wad_base + sizeof(int)*2; //johnfitz
 
diff --git a/Quake/gl_model.c b/Quake/gl_model.c
index c6b4906e..8c8dab2f 100644
--- a/Quake/gl_model.c
+++ b/Quake/gl_model.c
@@ -443,11 +443,11 @@ void Mod_LoadTextures (lump_t *l)
 				//external textures -- first look in "textures/mapname/" then look in "textures/"
 				mark = Hunk_LowMark();
 				COM_StripExtension (loadmodel->name + 5, mapname, sizeof(mapname));
-				sprintf (filename, "textures/%s/#%s", mapname, tx->name+1); //this also replaces the '*' with a '#'
+				q_snprintf (filename, sizeof(filename), "textures/%s/#%s", mapname, tx->name+1); //this also replaces the '*' with a '#'
 				data = Image_LoadImage (filename, &fwidth, &fheight);
 				if (!data)
 				{
-					sprintf (filename, "textures/#%s", tx->name+1);
+					q_snprintf (filename, sizeof(filename), "textures/#%s", tx->name+1);
 					data = Image_LoadImage (filename, &fwidth, &fheight);
 				}
 
@@ -460,7 +460,7 @@ void Mod_LoadTextures (lump_t *l)
 				}
 				else //use the texture from the bsp file
 				{
-					sprintf (texturename, "%s:%s", loadmodel->name, tx->name);
+					q_snprintf (texturename, sizeof(texturename), "%s:%s", loadmodel->name, tx->name);
 					offset = (src_offset_t)(mt+1) - (src_offset_t)mod_base;
 					tx->gltexture = TexMgr_LoadImage (loadmodel, texturename, tx->width, tx->height,
 						SRC_INDEXED, (byte *)(tx+1), loadmodel->name, offset, TEXPREF_NONE);
@@ -469,7 +469,7 @@ void Mod_LoadTextures (lump_t *l)
 				//now create the warpimage, using dummy data from the hunk to create the initial image
 				Hunk_Alloc (gl_warpimagesize*gl_warpimagesize*4); //make sure hunk is big enough so we don't reach an illegal address
 				Hunk_FreeToLowMark (mark);
-				sprintf (texturename, "%s_warp", texturename);
+				q_snprintf (texturename, sizeof(texturename), "%s_warp", texturename);
 				tx->warpimage = TexMgr_LoadImage (loadmodel, texturename, gl_warpimagesize,
 					gl_warpimagesize, SRC_RGBA, hunk_base, "", (src_offset_t)hunk_base, TEXPREF_NOPICMIP | TEXPREF_WARPIMAGE);
 				tx->update_warp = true;
@@ -479,11 +479,11 @@ void Mod_LoadTextures (lump_t *l)
 				//external textures -- first look in "textures/mapname/" then look in "textures/"
 				mark = Hunk_LowMark ();
 				COM_StripExtension (loadmodel->name + 5, mapname, sizeof(mapname));
-				sprintf (filename, "textures/%s/%s", mapname, tx->name);
+				q_snprintf (filename, sizeof(filename), "textures/%s/%s", mapname, tx->name);
 				data = Image_LoadImage (filename, &fwidth, &fheight);
 				if (!data)
 				{
-					sprintf (filename, "textures/%s", tx->name);
+					q_snprintf (filename, sizeof(filename), "textures/%s", tx->name);
 					data = Image_LoadImage (filename, &fwidth, &fheight);
 				}
 
@@ -495,10 +495,10 @@ void Mod_LoadTextures (lump_t *l)
 
 					//now try to load glow/luma image from the same place
 					Hunk_FreeToLowMark (mark);
-					sprintf (filename2, "%s_glow", filename);
+					q_snprintf (filename2, sizeof(filename2), "%s_glow", filename);
 					data = Image_LoadImage (filename2, &fwidth, &fheight);
 					if (!data)
-						sprintf (filename2, "%s_luma", filename);
+						q_snprintf (filename2, sizeof(filename2), "%s_luma", filename);
 						data = Image_LoadImage (filename2, &fwidth, &fheight);
 
 					if (data)
@@ -507,13 +507,13 @@ void Mod_LoadTextures (lump_t *l)
 				}
 				else //use the texture from the bsp file
 				{
-					sprintf (texturename, "%s:%s", loadmodel->name, tx->name);
+					q_snprintf (texturename, sizeof(texturename), "%s:%s", loadmodel->name, tx->name);
 					offset = (src_offset_t)(mt+1) - (src_offset_t)mod_base;
 					if (Mod_CheckFullbrights ((byte *)(tx+1), pixels))
 					{
 						tx->gltexture = TexMgr_LoadImage (loadmodel, texturename, tx->width, tx->height,
 							SRC_INDEXED, (byte *)(tx+1), loadmodel->name, offset, TEXPREF_MIPMAP | TEXPREF_NOBRIGHT);
-						sprintf (texturename, "%s:%s_glow", loadmodel->name, tx->name);
+						q_snprintf (texturename, sizeof(texturename), "%s:%s_glow", loadmodel->name, tx->name);
 						tx->fullbright = TexMgr_LoadImage (loadmodel, texturename, tx->width, tx->height,
 							SRC_INDEXED, (byte *)(tx+1), loadmodel->name, offset, TEXPREF_MIPMAP | TEXPREF_FULLBRIGHT);
 					}
@@ -1885,13 +1885,13 @@ void *Mod_LoadAllSkins (int numskins, daliasskintype_t *pskintype)
 			memcpy (texels, (byte *)(pskintype + 1), size);
 
 			//johnfitz -- rewritten
-			sprintf (name, "%s:frame%i", loadmodel->name, i);
+			q_snprintf (name, sizeof(name), "%s:frame%i", loadmodel->name, i);
 			offset = (src_offset_t)(pskintype+1) - (src_offset_t)mod_base;
 			if (Mod_CheckFullbrights ((byte *)(pskintype+1), size))
 			{
 				pheader->gltextures[i][0] = TexMgr_LoadImage (loadmodel, name, pheader->skinwidth, pheader->skinheight,
 					SRC_INDEXED, (byte *)(pskintype+1), loadmodel->name, offset, TEXPREF_PAD | TEXPREF_NOBRIGHT);
-				sprintf (fbr_mask_name, "%s:frame%i_glow", loadmodel->name, i);
+				q_snprintf (fbr_mask_name, sizeof(fbr_mask_name), "%s:frame%i_glow", loadmodel->name, i);
 				pheader->fbtextures[i][0] = TexMgr_LoadImage (loadmodel, fbr_mask_name, pheader->skinwidth, pheader->skinheight,
 					SRC_INDEXED, (byte *)(pskintype+1), loadmodel->name, offset, TEXPREF_PAD | TEXPREF_FULLBRIGHT);
 			}
@@ -1928,13 +1928,13 @@ void *Mod_LoadAllSkins (int numskins, daliasskintype_t *pskintype)
 				}
 
 				//johnfitz -- rewritten
-				sprintf (name, "%s:frame%i_%i", loadmodel->name, i,j);
+				q_snprintf (name, sizeof(name), "%s:frame%i_%i", loadmodel->name, i,j);
 				offset = (src_offset_t)(pskintype) - (src_offset_t)mod_base; //johnfitz
 				if (Mod_CheckFullbrights ((byte *)(pskintype), size))
 				{
 					pheader->gltextures[i][j&3] = TexMgr_LoadImage (loadmodel, name, pheader->skinwidth, pheader->skinheight,
 						SRC_INDEXED, (byte *)(pskintype), loadmodel->name, offset, TEXPREF_PAD | TEXPREF_NOBRIGHT);
-					sprintf (fbr_mask_name, "%s:frame%i_%i_glow", loadmodel->name, i,j);
+					q_snprintf (fbr_mask_name, sizeof(fbr_mask_name), "%s:frame%i_%i_glow", loadmodel->name, i,j);
 					pheader->fbtextures[i][j&3] = TexMgr_LoadImage (loadmodel, fbr_mask_name, pheader->skinwidth, pheader->skinheight,
 						SRC_INDEXED, (byte *)(pskintype), loadmodel->name, offset, TEXPREF_PAD | TEXPREF_FULLBRIGHT);
 				}
@@ -2265,7 +2265,7 @@ void * Mod_LoadSpriteFrame (void * pin, mspriteframe_t **ppframe, int framenum)
 	pspriteframe->tmax = (float)height/(float)TexMgr_PadConditional(height);
 	//johnfitz
 
-	sprintf (name, "%s:frame%i", loadmodel->name, framenum);
+	q_snprintf (name, sizeof(name), "%s:frame%i", loadmodel->name, framenum);
 	offset = (src_offset_t)(pinframe+1) - (src_offset_t)mod_base; //johnfitz
 	pspriteframe->gltexture =
 		TexMgr_LoadImage (loadmodel, name, width, height, SRC_INDEXED,
diff --git a/Quake/gl_rmisc.c b/Quake/gl_rmisc.c
index e6595310..c9d70b7d 100644
--- a/Quake/gl_rmisc.c
+++ b/Quake/gl_rmisc.c
@@ -305,7 +305,7 @@ void R_TranslateNewPlayerSkin (int playernum)
 	pixels = (byte *)paliashdr + paliashdr->texels[skinnum]; // This is not a persistent place!
 
 //upload new image
-	sprintf(name, "player_%i", playernum);
+	q_snprintf(name, sizeof(name), "player_%i", playernum);
 	playertextures[playernum] = TexMgr_LoadImage (currententity->model, name, paliashdr->skinwidth, paliashdr->skinheight,
 		SRC_INDEXED, pixels, paliashdr->gltextures[skinnum][0]->source_file, paliashdr->gltextures[skinnum][0]->source_offset, TEXPREF_PAD | TEXPREF_OVERWRITE);
 
diff --git a/Quake/gl_screen.c b/Quake/gl_screen.c
index 72e05c9c..ff720931 100644
--- a/Quake/gl_screen.c
+++ b/Quake/gl_screen.c
@@ -451,7 +451,7 @@ SCR_DrawClock -- johnfitz
 */
 void SCR_DrawClock (void)
 {
-	char	str[9];
+	char	str[12];
 
 	if (scr_clock.value == 1)
 	{
@@ -738,8 +738,8 @@ void SCR_ScreenShot_f (void)
 // find a file name to save it to
 	for (i=0; i<10000; i++)
 	{
-		sprintf (tganame, "spasm%04i.tga", i);	// "fitz%04i.tga"
-		sprintf (checkname, "%s/%s", com_gamedir, tganame);
+		q_snprintf (tganame, sizeof(tganame), "spasm%04i.tga", i);	// "fitz%04i.tga"
+		q_snprintf (checkname, sizeof(checkname), "%s/%s", com_gamedir, tganame);
 		if (Sys_FileTime(checkname) == -1)
 			break;	// file doesn't exist
 	}
diff --git a/Quake/gl_sky.c b/Quake/gl_sky.c
index d56e3259..a01780c5 100644
--- a/Quake/gl_sky.c
+++ b/Quake/gl_sky.c
@@ -105,7 +105,7 @@ void Sky_LoadTexture (texture_t *mt)
 		for (j=0 ; j<128 ; j++)
 			back_data[(i*128) + j] = src[i*256 + j + 128];
 
-	sprintf(texturename, "%s:%s_back", loadmodel->name, mt->name);
+	q_snprintf(texturename, sizeof(texturename), "%s:%s_back", loadmodel->name, mt->name);
 	solidskytexture = TexMgr_LoadImage (loadmodel, texturename, 128, 128, SRC_INDEXED, back_data, "", (src_offset_t)back_data, TEXPREF_NONE);
 
 // extract front layer and upload
@@ -117,7 +117,7 @@ void Sky_LoadTexture (texture_t *mt)
 				front_data[(i*128) + j] = 255;
 		}
 
-	sprintf(texturename, "%s:%s_front", loadmodel->name, mt->name);
+	q_snprintf(texturename, sizeof(texturename), "%s:%s_front", loadmodel->name, mt->name);
 	alphaskytexture = TexMgr_LoadImage (loadmodel, texturename, 128, 128, SRC_INDEXED, front_data, "", (src_offset_t)front_data, TEXPREF_ALPHA);
 
 // calculate r_fastsky color based on average of all opaque foreground colors
@@ -175,7 +175,7 @@ void Sky_LoadSkyBox (const char *name)
 	for (i=0; i<6; i++)
 	{
 		mark = Hunk_LowMark ();
-		sprintf (filename, "gfx/env/%s%s", name, suf[i]);
+		q_snprintf (filename, sizeof(filename), "gfx/env/%s%s", name, suf[i]);
 		data = Image_LoadImage (filename, &width, &height);
 		if (data)
 		{
diff --git a/Quake/gl_texmgr.c b/Quake/gl_texmgr.c
index a84cde38..bb46e65a 100644
--- a/Quake/gl_texmgr.c
+++ b/Quake/gl_texmgr.c
@@ -230,7 +230,7 @@ void TexMgr_Imagedump_f (void)
 	char *c;
 
 	//create directory
-	sprintf(dirname, "%s/imagedump", com_gamedir);
+	q_snprintf(dirname, sizeof(dirname), "%s/imagedump", com_gamedir);
 	Sys_mkdir (dirname);
 
 	//loop through textures
@@ -240,7 +240,7 @@ void TexMgr_Imagedump_f (void)
 		while ( (c = strchr(tempname, ':')) ) *c = '_';
 		while ( (c = strchr(tempname, '/')) ) *c = '_';
 		while ( (c = strchr(tempname, '*')) ) *c = '_';
-		sprintf(tganame, "imagedump/%s.tga", tempname);
+		q_snprintf(tganame, sizeof(tganame), "imagedump/%s.tga", tempname);
 
 		GL_Bind (glt);
 		if (glt->flags & TEXPREF_ALPHA)
diff --git a/Quake/host_cmd.c b/Quake/host_cmd.c
index d58ccc18..7e673458 100644
--- a/Quake/host_cmd.c
+++ b/Quake/host_cmd.c
@@ -189,7 +189,7 @@ void Host_Game_f (void)
 			//Load the paks if any are found:
 			for (i = 0; ; i++)
 			{
-				sprintf (pakfile, "%s/pak%i.pak", com_gamedir, i);
+				q_snprintf (pakfile, sizeof(pakfile), "%s/pak%i.pak", com_gamedir, i);
 				pak = COM_LoadPackFile (pakfile);
 				if (!pak)
 					break;
@@ -278,13 +278,13 @@ void ExtraMaps_Init (void)
 
 	// we don't want to list the maps in id1 pakfiles,
 	// because these are not "add-on" levels
-	sprintf (ignorepakdir, "/%s/", GAMENAME);
+	q_snprintf (ignorepakdir, sizeof(ignorepakdir), "/%s/", GAMENAME);
 
 	for (search = com_searchpaths; search; search = search->next)
 	{
 		if (*search->filename) //directory
 		{
-			sprintf (filestring,"%s/maps/",search->filename);
+			q_snprintf (filestring, sizeof(filestring), "%s/maps/", search->filename);
 			dir_p = opendir(filestring);
 			if (dir_p == NULL)
 				continue;
@@ -411,9 +411,9 @@ void Modlist_Init (void)
 
 	i = COM_CheckParm ("-basedir");
 	if (i && i < com_argc-1)
-		sprintf (dir_string, "%s/", com_argv[i+1]);
+		q_snprintf (dir_string, sizeof(dir_string), "%s/", com_argv[i+1]);
 	else
-		sprintf (dir_string, "%s/", host_parms->basedir);
+		q_snprintf (dir_string, sizeof(dir_string), "%s/", host_parms->basedir);
 
 	dir_p = opendir(dir_string);
 	if (dir_p == NULL)
@@ -423,7 +423,7 @@ void Modlist_Init (void)
 	{
 		if ((strcmp(dir_t->d_name, ".") == 0) || (strcmp(dir_t->d_name, "..") == 0))
 			continue;
-		sprintf(mod_dir_string, "%s%s/", dir_string, dir_t->d_name);
+		q_snprintf(mod_dir_string, sizeof(mod_dir_string), "%s%s/", dir_string, dir_t->d_name);
 		mod_dir_p = opendir(mod_dir_string);
 		if (mod_dir_p == NULL)
 			continue;
@@ -885,7 +885,7 @@ void Host_Changelevel_f (void)
 	}
 
 	//johnfitz -- check for client having map before anything else
-	sprintf (level, "maps/%s.bsp", Cmd_Argv(1));
+	q_snprintf (level, sizeof(level), "maps/%s.bsp", Cmd_Argv(1));
 	if (COM_OpenFile (level, &i, NULL) == -1)
 		Host_Error ("cannot find map %s", level);
 	//johnfitz
@@ -1047,7 +1047,7 @@ void Host_Savegame_f (void)
 		}
 	}
 
-	sprintf (name, "%s/%s", com_gamedir, Cmd_Argv(1));
+	q_snprintf (name, sizeof(name), "%s/%s", com_gamedir, Cmd_Argv(1));
 	COM_DefaultExtension (name, ".sav", sizeof(name));
 
 	Con_Printf ("Saving game to %s...\n", name);
@@ -1119,7 +1119,7 @@ void Host_Loadgame_f (void)
 
 	cls.demonum = -1;		// stop demo loop in case this fails
 
-	sprintf (name, "%s/%s", com_gamedir, Cmd_Argv(1));
+	q_snprintf (name, sizeof(name), "%s/%s", com_gamedir, Cmd_Argv(1));
 	COM_DefaultExtension (name, ".sav", sizeof(name));
 
 // we can't call SCR_BeginLoadingPlaque, because too much stack space has
diff --git a/Quake/image.c b/Quake/image.c
index 0a8ade32..91c4046e 100644
--- a/Quake/image.c
+++ b/Quake/image.c
@@ -37,12 +37,12 @@ byte *Image_LoadImage (const char *name, int *width, int *height)
 {
 	FILE	*f;
 
-	sprintf (loadfilename, "%s.tga", name);
+	q_snprintf (loadfilename, sizeof(loadfilename), "%s.tga", name);
 	COM_FOpenFile (loadfilename, &f, NULL);
 	if (f)
 		return Image_LoadTGA (f, width, height);
 
-	sprintf (loadfilename, "%s.pcx", name);
+	q_snprintf (loadfilename, sizeof(loadfilename), "%s.pcx", name);
 	COM_FOpenFile (loadfilename, &f, NULL);
 	if (f)
 		return Image_LoadPCX (f, width, height);
@@ -106,7 +106,7 @@ qboolean Image_WriteTGA (const char *name, byte *data, int width, int height, in
 	byte	header[TARGAHEADERSIZE];
 
 	Sys_mkdir (com_gamedir); //if we've switched to a nonexistant gamedir, create it now so we don't crash
-	sprintf (pathname, "%s/%s", com_gamedir, name);
+	q_snprintf (pathname, sizeof(pathname), "%s/%s", com_gamedir, name);
 	handle = Sys_FileOpenWrite (pathname);
 	if (handle == -1)
 		return false;
diff --git a/Quake/menu.c b/Quake/menu.c
index 73cd2f74..1038a618 100644
--- a/Quake/menu.c
+++ b/Quake/menu.c
@@ -431,7 +431,7 @@ void M_ScanSaves (void)
 	{
 		strcpy (m_filenames[i], "--- UNUSED SLOT ---");
 		loadable[i] = false;
-		sprintf (name, "%s/s%i.sav", com_gamedir, i);
+		q_snprintf (name, sizeof(name), "%s/s%i.sav", com_gamedir, i);
 		f = fopen (name, "r");
 		if (!f)
 			continue;
diff --git a/Quake/r_part.c b/Quake/r_part.c
index a2e15dae..7365c62c 100644
--- a/Quake/r_part.c
+++ b/Quake/r_part.c
@@ -269,7 +269,7 @@ void R_ReadPointFile_f (void)
 	particle_t	*p;
 	char	name[MAX_OSPATH];
 
-	sprintf (name,"maps/%s.pts", sv.name);
+	q_snprintf (name, sizeof(name), "maps/%s.pts", sv.name);
 
 	COM_FOpenFile (name, &f, NULL);
 	if (!f)
diff --git a/Quake/sv_main.c b/Quake/sv_main.c
index c445cac3..a2c3acc8 100644
--- a/Quake/sv_main.c
+++ b/Quake/sv_main.c
@@ -1354,8 +1354,8 @@ void SV_SpawnServer (const char *server)
 
 	sv.time = 1.0;
 
-	strcpy (sv.name, server);
-	sprintf (sv.modelname,"maps/%s.bsp", server);
+	strncpy (sv.name, server, sizeof(sv.name) - 1);
+	q_snprintf (sv.modelname, sizeof(sv.modelname), "maps/%s.bsp", server);
 	sv.worldmodel = Mod_ForName (sv.modelname, false);
 	if (!sv.worldmodel)
 	{