This paper presents a detailed review of research work on in-tube condensation in the literature due to its significance in refrigeration, air conditioning and heat pump applications. The heat transfer performance of heat exchangers can be improved by heat transfer enhancement techniques, such as active and passive techniques. Passive techniques requiring fluid additives or special surface geometries are mentioned in depth, by comparison with active techniques requiring external forces, e.g. electrical field, acoustic or surface vibration, etc., in the paper due to their common usage in condensation applications. In addition, the importance of usage of hydrocarbons instead of fluorocarbons is emphasised. This paper can not only be used as the starting point for the researcher interested in in-tube condensation process, but it also includes new investigations on condensation inside tubes. (C) 2009 Elsevier Ltd. All rights reserved.