Costa Rica is a remarkable place for amphibians and reptiles. Known for its biological diversity, conservation priorities, and extensive protected lands, this small country contains 418 herpetological species including the dangerous fer-de-lance and black-headed bushmaster, the biologically complex poison dart frog, the beloved sea turtles, as well as numerous dink, foam, glass, and rain frogs. Additional species are thought to be nearing extinction while others have only been introduced recently. The bilingual English/Spanish edition of Amphibians and Reptiles of Costa Rica is the perfect introductory guide to this diverse herpetofauna in a format that makes it easy to carry into the field. The focus is on identification with a complete species list for the country including scientific, English Common, and Spanish Common names, as well as the older names for the many species that have been recently reclassified. Key ID marks are noted as well as adult sizes. Range maps identify the region(s) where species are known to be present. Color photographs and drawings are provided for over 80 percent of the species, representing those that are most likely to be encountered. All text is in English and Spanish. Designed with ease of use in mind, this guide will be a great aid to the observer in identifying the specimen at hand.