Time-resolved light scattering represents a powerful tool to measure aggregation rate coefficients in colloidal dispersions. SLS as well as DLS can be used, even though DLS should be normally the method of choice, due to its better reproducibility, and the possibility to check the initial state of aggregation. The absolute rate coefficient can be obtained either by combining SLS and DLS, or by estimating the form factor and the hydrodynamic factor independently. Such estimates are rather straightforward, especially of smaller particles of low scattering power.