Heat and mass transfer, nucleation and growth on various substrates are considered (solid, liquid, plastic, undergoing phase change or micro-patterned substrates). The particular role of thermal or geometrical discontinuities where growth can be enhanced or reduced, dynamical aspects of self-diffusion, problems related to drop collection by gravity and the optics of dropwise condensation are all discussed. Although the content mainly deals with condensation from humid air, it can readily be generalized to condensation of any substance. The specificities of pure vapor condensation (e.g. steam) are also examined. Numerous images are provided within the text to illustrate the physics. This book is meant for those studying or researching dew and dropwise condensation, but also for individuals wishing to develop their knowledge on the subject.