This pen is just what we needed for a new puppy when she gets nippy! We step out of the pen and watch her from the lawn while she runs all around the pen. It's not as much space as anticipated but seems to work for her fine. Once she grows, higher, she'll be able to jump out! It was not difficult to assemble, although my husband says it is an added step to mow the lawn, as he has to move them out of the way and then set it up again.