In this course, accelerating social change, population ageing, and improved methodological tools are discussed in how they have allowed for extended knowledge, through the empirical examination of individual dynamics and societal shifts. In the course, relevant research methodologies for the study of life-course trajectories are introduced to further understand ageing processes, life-courses, and social change across individual and historical times. Furthermore, the role of time, in social research and relevant research methodologies are addressed. During the course a theoretical base within fundamental principles of research and research methods (for example cross-sectional and longitudinal studies), macro-, mezzo- and microdata, sampling and measurements are presented. Ethical considerations are also addressed, and the implications and challenges currently faced when conducting and interpreting life-course studies.