The present work is a compilation of the systematics of the genus Hoplolaimus (Nematoda: Hoplolaimidae) including all currently 37 valid species which are reported worldwide. They are plant parasites living in the soil, causing damage to plants and have an economic importance. For each species, morphometric data, descriptions of females, males and juveniles (whenever present), relationships with close species, and their distribution (host plants and localities) are discussed. The book is amply illustrated with drawings obtained from microscopic observations in the literature. An Identification key to the species is included. This book hopefully will help students, nematologists and other interested academic disciplines with the identifications of these nematodes to species level.