static void Main(string[] args) { new DB("assets"); var client = new Client { Name = "Marco Polo", Assets = new Asset[] { new Asset { Name = "asset one", Enabled = true }, new Asset { Name = "asset two", Enabled = true }, new Asset { Name = "asset three", Enabled = true } } }; client.Save(); var clientID = client.ID; var result = client.Collection() .Where(c => c.ID == clientID) .SelectMany(c => c.Assets) .ToArray(); Console.ReadKey(); }