diff --git a/DnsServerCore/Dns/ZoneManagers/BlockListZoneManager.cs b/DnsServerCore/Dns/ZoneManagers/BlockListZoneManager.cs
index ea9d172c..c36f43ff 100644
--- a/DnsServerCore/Dns/ZoneManagers/BlockListZoneManager.cs
+++ b/DnsServerCore/Dns/ZoneManagers/BlockListZoneManager.cs
@@ -38,6 +38,7 @@ namespace DnsServerCore.Dns.ZoneManagers
         readonly DnsServer _dnsServer;
         readonly string _localCacheFolder;
 
+        readonly List<Uri> _allowListUrls = new List<Uri>();
         readonly List<Uri> _blockListUrls = new List<Uri>();
         IReadOnlyDictionary<string, List<Uri>> _blockListZone = new Dictionary<string, List<Uri>>();
 
@@ -105,7 +106,7 @@ namespace DnsServerCore.Dns.ZoneManagers
             return word;
         }
 
-        private Queue<string> ReadBlockListFile(Uri blockListUrl)
+        private Queue<string> ReadListFile(Uri listUrl, bool isAllow)
         {
             Queue<string> domains = new Queue<string>();
 
@@ -113,9 +114,9 @@ namespace DnsServerCore.Dns.ZoneManagers
             {
                 LogManager log = _dnsServer.LogManager;
                 if (log != null)
-                    log.Write("DNS Server is reading block list from: " + blockListUrl.AbsoluteUri);
+                    log.Write("DNS Server is reading " + (isAllow ? "allow" : "block") + " list from: " + listUrl.AbsoluteUri);
 
-                using (FileStream fS = new FileStream(GetBlockListFilePath(blockListUrl), FileMode.Open, FileAccess.Read))
+                using (FileStream fS = new FileStream(GetBlockListFilePath(listUrl), FileMode.Open, FileAccess.Read))
                 {
                     //parse hosts file and populate block zone
                     StreamReader sR = new StreamReader(fS, true);
@@ -185,13 +186,13 @@ namespace DnsServerCore.Dns.ZoneManagers
                 }
 
                 if (log != null)
-                    log.Write("DNS Server block list file was read (" + domains.Count + " domains) from: " + blockListUrl.AbsoluteUri);
+                    log.Write("DNS Server " + (isAllow ? "allow" : "block") + " list file was read (" + domains.Count + " domains) from: " + listUrl.AbsoluteUri);
             }
             catch (Exception ex)
             {
                 LogManager log = _dnsServer.LogManager;
                 if (log != null)
-                    log.Write("DNS Server failed to read block list from: " + blockListUrl.AbsoluteUri + "\r\n" + ex.ToString());
+                    log.Write("DNS Server failed to read " + (isAllow ? "allow" : "block") + " list from: " + listUrl.AbsoluteUri + "\r\n" + ex.ToString());
             }
 
             return domains;
@@ -225,6 +226,21 @@ namespace DnsServerCore.Dns.ZoneManagers
 
         public void LoadBlockLists()
         {
+            //read all allowed domains in dictionary
+            Dictionary<string, object> allowedDomains = new Dictionary<string, object>();
+
+            foreach (Uri allowListUri in _allowListUrls)
+            {
+                Queue<string> queue = ReadListFile(allowListUri, true);
+
+                while (queue.Count > 0)
+                {
+                    string domain = queue.Dequeue();
+
+                    allowedDomains.TryAdd(domain, null);
+                }
+            }
+
             //read all block lists in a queue
             Dictionary<Uri, Queue<string>> blockListQueues = new Dictionary<Uri, Queue<string>>(_blockListUrls.Count);
             int totalDomains = 0;
@@ -233,7 +249,7 @@ namespace DnsServerCore.Dns.ZoneManagers
             {
                 if (!blockListQueues.ContainsKey(blockListUrl))
                 {
-                    Queue<string> blockListQueue = ReadBlockListFile(blockListUrl);
+                    Queue<string> blockListQueue = ReadListFile(blockListUrl, false);
                     totalDomains += blockListQueue.Count;
                     blockListQueues.Add(blockListUrl, blockListQueue);
                 }
@@ -250,6 +266,9 @@ namespace DnsServerCore.Dns.ZoneManagers
                 {
                     string domain = queue.Dequeue();
 
+                    if (allowedDomains.TryGetValue(domain, out _))
+                        continue; //domain is in allowed list so skip adding it to block list zone
+
                     if (!blockListZone.TryGetValue(domain, out List<Uri> blockLists))
                     {
                         blockLists = new List<Uri>(2);
@@ -278,15 +297,15 @@ namespace DnsServerCore.Dns.ZoneManagers
             bool downloaded = false;
             bool notmodified = false;
 
-            foreach (Uri blockListUrl in _blockListUrls)
+            async Task DownloadListUrlAsync(Uri listUrl, bool isAllowList)
             {
-                string blockListFilePath = GetBlockListFilePath(blockListUrl);
-                string blockListDownloadFilePath = blockListFilePath + ".downloading";
+                string listFilePath = GetBlockListFilePath(listUrl);
+                string listDownloadFilePath = listFilePath + ".downloading";
 
                 try
                 {
-                    if (File.Exists(blockListDownloadFilePath))
-                        File.Delete(blockListDownloadFilePath);
+                    if (File.Exists(listDownloadFilePath))
+                        File.Delete(listDownloadFilePath);
 
                     HttpClientHandler handler = new HttpClientHandler();
                     handler.Proxy = _dnsServer.Proxy;
@@ -294,33 +313,33 @@ namespace DnsServerCore.Dns.ZoneManagers
 
                     using (HttpClient http = new HttpClient(handler))
                     {
-                        if (File.Exists(blockListFilePath))
-                            http.DefaultRequestHeaders.IfModifiedSince = File.GetLastWriteTimeUtc(blockListFilePath);
+                        if (File.Exists(listFilePath))
+                            http.DefaultRequestHeaders.IfModifiedSince = File.GetLastWriteTimeUtc(listFilePath);
 
-                        HttpResponseMessage httpResponse = await http.GetAsync(blockListUrl);
+                        HttpResponseMessage httpResponse = await http.GetAsync(listUrl);
                         switch (httpResponse.StatusCode)
                         {
                             case HttpStatusCode.OK:
                                 {
-                                    using (FileStream fS = new FileStream(blockListDownloadFilePath, FileMode.Create, FileAccess.Write))
+                                    using (FileStream fS = new FileStream(listDownloadFilePath, FileMode.Create, FileAccess.Write))
                                     {
                                         Stream httpStream = await httpResponse.Content.ReadAsStreamAsync();
                                         await httpStream.CopyToAsync(fS);
                                     }
 
-                                    if (File.Exists(blockListFilePath))
-                                        File.Delete(blockListFilePath);
+                                    if (File.Exists(listFilePath))
+                                        File.Delete(listFilePath);
 
-                                    File.Move(blockListDownloadFilePath, blockListFilePath);
+                                    File.Move(listDownloadFilePath, listFilePath);
 
                                     if (httpResponse.Content.Headers.LastModified != null)
-                                        File.SetLastWriteTimeUtc(blockListFilePath, httpResponse.Content.Headers.LastModified.Value.UtcDateTime);
+                                        File.SetLastWriteTimeUtc(listFilePath, httpResponse.Content.Headers.LastModified.Value.UtcDateTime);
 
                                     downloaded = true;
 
                                     LogManager log = _dnsServer.LogManager;
                                     if (log != null)
-                                        log.Write("DNS Server successfully downloaded block list (" + WebUtilities.GetFormattedSize(new FileInfo(blockListFilePath).Length) + "): " + blockListUrl.AbsoluteUri);
+                                        log.Write("DNS Server successfully downloaded " + (isAllowList ? "allow" : "block") + " list (" + WebUtilities.GetFormattedSize(new FileInfo(listFilePath).Length) + "): " + listUrl.AbsoluteUri);
                                 }
                                 break;
 
@@ -330,7 +349,7 @@ namespace DnsServerCore.Dns.ZoneManagers
 
                                     LogManager log = _dnsServer.LogManager;
                                     if (log != null)
-                                        log.Write("DNS Server successfully checked for a new update of the block list: " + blockListUrl.AbsoluteUri);
+                                        log.Write("DNS Server successfully checked for a new update of the " + (isAllowList ? "allow" : "block") + " list: " + listUrl.AbsoluteUri);
                                 }
                                 break;
 
@@ -343,10 +362,20 @@ namespace DnsServerCore.Dns.ZoneManagers
                 {
                     LogManager log = _dnsServer.LogManager;
                     if (log != null)
-                        log.Write("DNS Server failed to download block list and will use previously downloaded file (if available): " + blockListUrl.AbsoluteUri + "\r\n" + ex.ToString());
+                        log.Write("DNS Server failed to download " + (isAllowList ? "allow" : "block") + " list and will use previously downloaded file (if available): " + listUrl.AbsoluteUri + "\r\n" + ex.ToString());
                 }
             }
 
+            List<Task> tasks = new List<Task>();
+
+            foreach (Uri allowListUrl in _allowListUrls)
+                tasks.Add(DownloadListUrlAsync(allowListUrl, true));
+
+            foreach (Uri blockListUrl in _blockListUrls)
+                tasks.Add(DownloadListUrlAsync(blockListUrl, false));
+
+            await Task.WhenAll(tasks);
+
             if (downloaded)
             {
                 LoadBlockLists();
@@ -412,6 +441,9 @@ namespace DnsServerCore.Dns.ZoneManagers
             set { UpdateServerDomain(value); }
         }
 
+        public List<Uri> AllowListUrls
+        { get { return _allowListUrls; } }
+
         public List<Uri> BlockListUrls
         { get { return _blockListUrls; } }