The Above is an IList itself as this is what seems to be the standard to use with nhibernate. Otherwise I might have returned IEnumberable back but not sure. Still, I hayat't figure out what the user would 100% need(that's where returning a concrete başmaklık an advantage over). C# CollectionBase https://edgarzimpt.blogitright.com/28153712/c-ilist-nerelerde-kullanılıyor-ile-ilgili-detaylı-notlar