This book discusses an amazing genus of lizards in Yemen. This group includes the famous genus of Arabia which is 'Hemidactylus'. Hemidactylus Oken, 1817 is widely distributed and considered one of the most species-rich genera of the family Gekkonidae which contains recently around 140 species.This book presents information concerning Yemen. This region has a special geographical position between the Arabian Peninsula and Africa, and is considered the junction point of the Red sea and Arabian Sea. This location has given Yemen different climatic features, in addition to the variety of the topography in the country. These factors are favorable for the existence of diverse ecosystems along with a high level of biodiversity.