A new generation of durable goods makes an old generation economically, even if not physically, obsolete. Economic obsolescence due to technological innovation requires the durable goods monopolist to implement price discrimination in two dimensions, both between consumers with different valuations and between consumers with different purchase histories. Equilibrium in the game between the durable goods monopolist and consumers depends on the extent of economic obsolescence and the relative sizes of the consumer groups. Underinvestment in innovation may take place. This contrasts with the standard literature on planned obsolescence where the durable goods monopolist overinvests in durability reducing technology.