Laurence van Cott Niven's best known work is Ringworld (Ringworld, #1) (1970), which received the Hugo, Locus, Ditmar, and Nebula awards. His work is primarily hard science fiction, using big science concepts and theoretical physics. The creation of thoroughly worked-out alien species, which are very different from humans both physically and mentally, is recognized as one of Niven's main strengths.

Niven also often includes elements of detective fiction and adventure stories. His fantasy includes The Magic Goes Away series, which utilizes an exhaustible resource, called Mana, to make the magic a non-renewable resource.

Niven created an alien species, the Kzin, which were featured in a series of twelve collection books, the Man-Kzin Wars. He