This work reports several aspects concerning dynamic light scattering data of apoprotein A-I in solution. Using the geometrical factor (H) and turbidity (τ) at different pH values ranging from 5 to 10, we have tried to elucidate either if the initial formation of clusters and the trend for aggregation are carried out by nucleation or random mechanisms. Taking into account the solubility of the protein, this behavior depends on the precipitating agent used and the rate of mass transporting capacity carried out by vapor diffusion in small drops. Finally, we demonstrate that dynamic light scattering is a useful tool in order to determine protein precrystallization conditions.