in a cross-sequential design (also called an "accelerated longitudinal" or "convergence" design), a researcher wants to study development over some large period of time within the lifespan. rather than studying particular individuals across that whole period of time (e.g. 20–60 years) as in a longitudinal design, or multiple individuals of different ages at one time (e.g. 20, 25, 30, 35, 40, 45, 50, 55, and 60 years) as in a cross-sectional design, the researcher chooses a smaller time window (e.g. 20 years) to study multiple individuals of different starting ages. an example of a cross-sequential design is shown in the table below.