Small heat shock proteins (sHsp) are a class of molecular chaperones that are upregulated in response to cellular stress to prevent the aberrant aggregation of misfolded proteins and thus the progression of diseases associated with protein aggregation, such as Parkinson’s and Alzheimer’s disease. Although it’s widely suggested that sHsps prevent aggregation by binding to misfolded, yet folding-competent, client proteins, their dynamic and heterogeneous nature has previously meant that mechanistic details surrounding this function remains unclear. Therefore, the interactions between sHsps and their clients are ideally suited to investigation using single molecule techniques. We have exploited total internal reflection fluorescence microscopy to monitor the photobleaching of single fluorophores attached to the model aggregation-prone client proteins firefly luciferase (FLUC), rhodanese, and chloride intracellular channel 1 protein (CLIC1), and the sHsps αB-crystallin (αB-c) and Hsp27. In doing so, we were able to monitor the formation of client-sHsp complexes and record temporal changes in the stoichiometries within these complexes. We found that small (monomeric or dimeric) forms of αB-c and Hsp27 bind to misfolded clients early during aggregation, resulting in the formation of soluble client-sHsp complexes. Furthermore, stoichiometric analysis revealed that αB-c accumulates onto existing client-sHsp complexes to form larger species, whereas Hsp27 does not, which suggests Hsp27 may interact transiently with misfolded clients to prevent their aggregation. Elucidating these mechanisms of sHsp function is crucial to our understanding of how they maintain proteostasis, and could not be determined using conventional ensemble averaging approaches.