 This paper provides a comprehensive guide to estimating daily and monthly actual, potential, reference crop and pan evaporation. It covers topics of interest to researchers, consulting hydrologists and practicing engineers. The paper begins with a discussion of theoretical concepts and outlines the Penman-Monteith, Priestley, Taylor and Class A pan models. It then moves on to practical applications, including techniques for estimating actual evaporation from open surface waters, lakes, farms and catchments. Additionally, it explores methods for calculating evaporation rates from deep lakes, shallow lakes and farm dams, as well as those for irrigated areas and bare soils. Finally, the paper concludes with a section on six related topics, including automatic calculation of evaporation estimates in commercial weather stations, evaporation estimates without wind data, at-site meteorological data, dealing with evaporation in a climate change environment, 24 H versus daylight hour estimation of meteorological variables, and uncertainty in evaporation estimates. This article was authored by T. A. McMahon, M. C. Peel, L. Lowe and others. We are article.tv, links in the description below.