This section explains why land rent is analytically difficult and then traces the historical transformation of land rent from feudal forms to capitalist money rent. It argues that economic analysis often begins with industry because capitalist relations are typically more fully developed there, and then applies commodity analysis to agriculture, where rent appears as a distinct form of surplus. The section distinguishes labor rent, rent in kind, and money rent, and specifies the social conditions required for the transition to capitalist land rent: commercialization of agricultural output, monetization and contractualization of tenancy relations, separation of producers from traditional feudal obligations, and the formation of an average profit rate that regulates the division of agricultural surplus. On this basis, it shows how excess profit in agriculture is transformed into land rent under capitalist conditions and notes that, in concrete historical transitions, these forms often appear in complex and unfinished combinations.