Public health adaptation to climate change is an important issue and inevitably is needed to address the adverse health impacts of climate change over the next few decades. This paper provides an overview of the constraints and barriers to public health adaptation and explores future research directions in this emerging field. An extensive literature review was conducted in 2010 and published literature from 2000 to 2010 was retrieved. This review shows that public health adaptation essentially can operate at two levels, namely, adaptive-capacity building and implementation of adaptation actions. However, there are constraints and barriers to public health adaptation arising from uncertainties of future climate and socioeconomic conditions, as well as financial, technologic, institutional, social capital, and individual cognitive limits. The opportunities for planning and implementing public health adaptation are reliant on effective strategies to overcome these constraints and barriers. It is proposed here that high research priority should be given to multidisciplinary research on the assessment of potential health impacts of climate change, projections of health impacts under different climate and socioeconomic scenarios, identification of health co-benefits of mitigation strategies, and evaluation of cost-effective public health adaptation options.