The guide's objectives include: consideration of the cognitive and developmental changes that occur during early adolescence and what impact they may have on the design of a research study; review of ethical issues to be considered before research with VYAs is conducted; exploration of the breadth and limitations of information that can be gleaned from existing data sets such as the Demographic and Health Surveys; introduction of a number of research methodologies that have been tested already with younger adolescents or that might be expected to be useful in some settings, with discussion of their advantages and limitations; description of research results on VYAs that have been achieved using these methodologies; and provision of illustrative prototype tools and basic instructions for using them.