In this paper we describe the knowledge-based recommender application FSAdvisor (Financial Services Advisor) which assists sales representatives in determining personalized financial service portfolios for their customers. Commercially introduced in 2003, FSAdvisor is licensed to a number of major financial service providers in Austria. It supports the dialog between a sales representative and a customer by guaranteeing the consistency and appropriateness of proposed solutions, identifying additional selling opportunities and by providing intelligent explanations for solutions. In the financial services domain (especially in the retail sector) sales representatives can differ greatly in their expertise and level of knowledge. Therefore financial service providers ask for tools effectively supporting sales representatives in the dialog with the customer. Knowledge-based recommender approaches meet these requirements by allowing an intuitive and flexible mapping of marketing and sales knowledge to the representation of a recommender knowledge base. In FSAdvisor we integrate model-based diagnosis, constraint satisfaction and personalization thus supporting customer-oriented sales dialogs. A graphical development environment enables the implementation of financial service knowledge bases for non-programmers which leads to significant reductions of development and maintenance costs.