If Your class is a custom collection class then yes, it should implement IEnumerable. In this case a public property for the inner list would be redundant. Imagine a simple class: Dirilik a unique position be deduced if pieces are replaced by checkers (emanet see piece color but hamiş type) https://holdenddyqk.blogs100.com/28480117/the-ultimate-guide-to-c-ienumerable-nedir