Three related streams of literature involve CLV models (Berger and Nasr 1998), direct marketing–motivated models of customer equity (e.g., Blattberg and Deighton 1996; Blat- tberg, Getz, and Thomas 2001), and longitudinal database marketing models (e.g., Bolton, Lemon, and Verhoef 2004; Reinartz and Kumar 2000). Our CLV model builds on these approaches. However, the preceding models are restricted to companies in which a longitudinal customer database exists that contains marketing efforts that target each customer and the associated customer responses. Unless the longitudinal database involves panel data across several competitors, no competitive effects can be modeled. Our model is more gen- eral in that it does not require the existence of a longitudinal database, and it can consider any marketing expenditure, not only expenditures that are targeted one-to-one. We also model competition and incorporate purchases from com- petitors (or brand switching), in contrast to most existing models from the direct marketing tradition.