The aging workforce will soon lead to a number of retirements in Small and Medium-Sized Enterprises (SMEs) that cannot be compensated for by the decreasing pool of succeeding individuals. Consequently, SMEs need to find ways to cope with the demographic challenge and its possible consequences. Otherwise, its capability to act is at risk in situations when critical staff is leaving. This clearly illustrates the need for a proper succession planning. One that takes into consideration the knowledge at stake. The aim of this chapter is to draw attention to the danger of knowledge loss as a consequence of an aging workforce and to discuss three approaches SMEs can use to better understand the knowledge at risk. Set against the importance of SMEs in most of the world, the study's results provide relevant insights into how to cope with knowledge at risk in order to secure the firms' survivability.