This article addresses the issue of training next-generation family members once they have joined the management team in their family firm. The qualitative analysis of strategic planning processes of 18 Italian family firms shows that involving next-generation family members in the planning process benefits their developmental process. The findings indicate that this involvement provides the next generation with crucial tacit business knowledge and skills, facilitating interpersonal work relationships between incumbents and next-generation leaders and building credibility and legitimacy for the next generation. The comparative analysis of the cases allowed us to identify the five variables that seem to combine in explaining much of the observed differences in the amount and composition of benefits experienced in the 18 firms. Our findings extend current understanding of two understudied topics in family business: the postentry-phase training of the next generation and strategic management in family firms.