There are two types of object cloning; deep and shallow.

A shallow clone creates a new instance of the same type as the original object, with all its value-typed fields copied. However, the reference type fields still point to the original objects; and so the "new" object and the original reference to the same object. On the other hand, a deep clone of an object contains a full copy of everything directly or indirectly referenced by the object - and so you get a "true" copy.

One of the easiest ways to deep-copy an object is to serialize the object into memory and de-serialize it again - although this does require the object graph to be serializable. Here's a handy code snippet to do this:

public static object CloneObject(object obj)
{
    using (MemoryStream memStream = new MemoryStream())
    {
        BinaryFormatter binaryFormatter = new BinaryFormatter(null, 
             new StreamingContext(StreamingContextStates.Clone));
        binaryFormatter.Serialize(memStream, obj);
        memStream.Seek(0, SeekOrigin.Begin);
        return binaryFormatter.Deserialize(memStream);
    }
}

You could then implement the ICloneable interface on your object like so:

public class MyObject  : ICloneable {
    public object Clone()
    {
        return ObjectUtility.CloneObject(this);
    }
    ...
}