diff --git a/src/Core/Models/Domain/Collection.cs b/src/Core/Models/Domain/Collection.cs
index b917c2207..5e0578507 100644
--- a/src/Core/Models/Domain/Collection.cs
+++ b/src/Core/Models/Domain/Collection.cs
@@ -33,9 +33,9 @@ namespace Bit.Core.Models.Domain
         public string ExternalId { get; set; }
         public bool ReadOnly { get; set; }
 
-        public Task<CollectionView> DecryptAsync(string orgId)
+        public Task<CollectionView> DecryptAsync()
         {
-            return DecryptObjAsync(new CollectionView(this), this, new HashSet<string> { "Name" }, orgId);
+            return DecryptObjAsync(new CollectionView(this), this, new HashSet<string> { "Name" }, OrganizationId);
         }
     }
 }
diff --git a/src/Core/Services/CollectionService.cs b/src/Core/Services/CollectionService.cs
new file mode 100644
index 000000000..4fdff9432
--- /dev/null
+++ b/src/Core/Services/CollectionService.cs
@@ -0,0 +1,245 @@
+using Bit.Core.Abstractions;
+using Bit.Core.Models.Data;
+using Bit.Core.Models.Domain;
+using Bit.Core.Models.View;
+using Bit.Core.Utilities;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text.RegularExpressions;
+using System.Threading.Tasks;
+
+namespace Bit.Core.Services
+{
+    public class CollectionService
+    {
+        private const string Keys_CollectionsFormat = "collections_{0}";
+        private const char NestingDelimiter = '/';
+
+        private List<CollectionView> _decryptedCollectionCache;
+        private readonly ICryptoService _cryptoService;
+        private readonly IUserService _userService;
+        private readonly IApiService _apiService;
+        private readonly IStorageService _storageService;
+        private readonly II18nService _i18nService;
+        private readonly ICipherService _cipherService;
+
+        public CollectionService(
+            ICryptoService cryptoService,
+            IUserService userService,
+            IApiService apiService,
+            IStorageService storageService,
+            II18nService i18nService,
+            ICipherService cipherService)
+        {
+            _cryptoService = cryptoService;
+            _userService = userService;
+            _apiService = apiService;
+            _storageService = storageService;
+            _i18nService = i18nService;
+            _cipherService = cipherService;
+        }
+
+        public void ClearCache()
+        {
+            _decryptedCollectionCache = null;
+        }
+
+        public async Task<Collection> EncryptAsync(CollectionView model)
+        {
+            if(model.OrganizationId == null)
+            {
+                throw new Exception("Collection has no organization id.");
+            }
+            var key = await _cryptoService.GetOrgKeyAsync(model.OrganizationId);
+            if(key == null)
+            {
+                throw new Exception("No key for this collection's organization.");
+            }
+            var collection = new Collection
+            {
+                Id = model.Id,
+                OrganizationId = model.OrganizationId,
+                ReadOnly = model.ReadOnly,
+                Name = await _cryptoService.EncryptAsync(model.Name, key)
+            };
+            return collection;
+        }
+
+        public async Task<List<CollectionView>> DecryptManyAsync(List<Collection> collections)
+        {
+            if(collections == null)
+            {
+                return new List<CollectionView>();
+            }
+            var decCollections = new List<CollectionView>();
+            var tasks = new List<Task>();
+            foreach(var collection in collections)
+            {
+                tasks.Add(collection.DecryptAsync().ContinueWith(async c => decCollections.Add(await c)));
+            }
+            await Task.WhenAll(tasks);
+            return decCollections.OrderBy(c => c, new CollectionLocaleComparer(_i18nService)).ToList();
+        }
+
+        public async Task<Collection> GetAsync(string id)
+        {
+            var userId = await _userService.GetUserIdAsync();
+            var collections = await _storageService.GetAsync<Dictionary<string, CollectionData>>(
+                string.Format(Keys_CollectionsFormat, userId));
+            if(!collections?.ContainsKey(id) ?? true)
+            {
+                return null;
+            }
+            return new Collection(collections[id]);
+        }
+
+        public async Task<List<Collection>> GetAllAsync()
+        {
+            var userId = await _userService.GetUserIdAsync();
+            var collections = await _storageService.GetAsync<Dictionary<string, CollectionData>>(
+                string.Format(Keys_CollectionsFormat, userId));
+            var response = collections.Select(c => new Collection(c.Value));
+            return response.ToList();
+        }
+
+        // TODO: sequentialize?
+        public async Task<List<CollectionView>> GetAllDecryptedAsync()
+        {
+            if(_decryptedCollectionCache != null)
+            {
+                return _decryptedCollectionCache;
+            }
+            var hasKey = await _cryptoService.HasKeyAsync();
+            if(!hasKey)
+            {
+                throw new Exception("No key.");
+            }
+            var collections = await GetAllAsync();
+            _decryptedCollectionCache = await DecryptManyAsync(collections);
+            return _decryptedCollectionCache;
+        }
+
+        public async Task<List<TreeNode<CollectionView>>> GetAllNestedAsync(List<CollectionView> collections = null)
+        {
+            if(collections == null)
+            {
+                collections = await GetAllDecryptedAsync();
+            }
+            var nodes = new List<TreeNode<CollectionView>>();
+            foreach(var c in collections)
+            {
+                var collectionCopy = new CollectionView
+                {
+                    Id = c.Id,
+                    OrganizationId = c.OrganizationId
+                };
+                CoreHelpers.NestedTraverse(nodes, 0,
+                    Regex.Replace(c.Name, "^\\/+|\\/+$", string.Empty).Split(NestingDelimiter),
+                    collectionCopy, null, NestingDelimiter);
+            }
+            return nodes;
+        }
+
+        public async Task<TreeNode<CollectionView>> GetNestedAsync(string id)
+        {
+            var collections = await GetAllNestedAsync();
+            return CoreHelpers.GetTreeNodeObject(collections, id);
+        }
+
+        public async Task UpsertAsync(CollectionData collection)
+        {
+            var userId = await _userService.GetUserIdAsync();
+            var storageKey = string.Format(Keys_CollectionsFormat, userId);
+            var collections = await _storageService.GetAsync<Dictionary<string, CollectionData>>(storageKey);
+            if(collections == null)
+            {
+                collections = new Dictionary<string, CollectionData>();
+            }
+            if(!collections.ContainsKey(collection.Id))
+            {
+                collections.Add(collection.Id, null);
+            }
+            collections[collection.Id] = collection;
+            await _storageService.SaveAsync(storageKey, collections);
+            _decryptedCollectionCache = null;
+        }
+
+        public async Task UpsertAsync(List<CollectionData> collection)
+        {
+            var userId = await _userService.GetUserIdAsync();
+            var storageKey = string.Format(Keys_CollectionsFormat, userId);
+            var collections = await _storageService.GetAsync<Dictionary<string, CollectionData>>(storageKey);
+            if(collections == null)
+            {
+                collections = new Dictionary<string, CollectionData>();
+            }
+            foreach(var c in collection)
+            {
+                if(!collections.ContainsKey(c.Id))
+                {
+                    collections.Add(c.Id, null);
+                }
+                collections[c.Id] = c;
+            }
+            await _storageService.SaveAsync(storageKey, collections);
+            _decryptedCollectionCache = null;
+        }
+
+        public async Task ReplaceAsync(Dictionary<string, CollectionData> collections)
+        {
+            var userId = await _userService.GetUserIdAsync();
+            await _storageService.SaveAsync(string.Format(Keys_CollectionsFormat, userId), collections);
+            _decryptedCollectionCache = null;
+        }
+
+        public async Task ClearAsync(string userId)
+        {
+            await _storageService.RemoveAsync(string.Format(Keys_CollectionsFormat, userId));
+            _decryptedCollectionCache = null;
+        }
+
+        public async Task DeleteAsync(string id)
+        {
+            var userId = await _userService.GetUserIdAsync();
+            var collectionKey = string.Format(Keys_CollectionsFormat, userId);
+            var collections = await _storageService.GetAsync<Dictionary<string, CollectionData>>(collectionKey);
+            if(collections == null || !collections.ContainsKey(id))
+            {
+                return;
+            }
+            collections.Remove(id);
+            await _storageService.SaveAsync(collectionKey, collections);
+            _decryptedCollectionCache = null;
+        }
+
+        private class CollectionLocaleComparer : IComparer<CollectionView>
+        {
+            private readonly II18nService _i18nService;
+
+            public CollectionLocaleComparer(II18nService i18nService)
+            {
+                _i18nService = i18nService;
+            }
+
+            public int Compare(CollectionView a, CollectionView b)
+            {
+                var aName = a.Name;
+                var bName = b.Name;
+                if(aName == null && bName != null)
+                {
+                    return -1;
+                }
+                if(aName != null && bName == null)
+                {
+                    return 1;
+                }
+                if(aName == null && bName == null)
+                {
+                    return 0;
+                }
+                return _i18nService.StringComparer.Compare(aName, bName);
+            }
+        }
+    }
+}
diff --git a/src/Core/Services/FolderService.cs b/src/Core/Services/FolderService.cs
index 154a5ccca..2d2a6bb57 100644
--- a/src/Core/Services/FolderService.cs
+++ b/src/Core/Services/FolderService.cs
@@ -8,6 +8,7 @@ using Bit.Core.Utilities;
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using System.Text.RegularExpressions;
 using System.Threading.Tasks;
 
 namespace Bit.Core.Services
@@ -85,8 +86,8 @@ namespace Bit.Core.Services
             {
                 return _decryptedFolderCache;
             }
-            var hashKey = await _cryptoService.HasKeyAsync();
-            if(!hashKey)
+            var hasKey = await _cryptoService.HasKeyAsync();
+            if(!hasKey)
             {
                 throw new Exception("No key.");
             }
@@ -121,8 +122,9 @@ namespace Bit.Core.Services
                     Id = f.Id,
                     RevisionDate = f.RevisionDate
                 };
-                CoreHelpers.NestedTraverse(nodes, 0, f.Name.Split(NestingDelimiter), folderCopy, null,
-                    NestingDelimiter);
+                CoreHelpers.NestedTraverse(nodes, 0,
+                    Regex.Replace(f.Name, "^\\/+|\\/+$", string.Empty).Split(NestingDelimiter),
+                    folderCopy, null, NestingDelimiter);
             }
             return nodes;
         }