Spanish Abstract: Hay normas de gobierno de productos, que condicionan la produccion y distribucion de los prestamos a la satisfaccion de las necesidades de los clientes a los que se destinan, y unas normas de conducta, de conocer al cliente, evaluarle y suministrarle por personal cualificado informacion clara y comprensible sobre el producto ofrecido. En este capitulo nos vamos a ocupar de la obligacion de evaluacion de la solvencia del potencial prestatario. La correcta evaluacion requiere conocer al cliente y para conocer al cliente es necesario evaluarlo con profesionalidad. English Abstract:There are rules of product governance which condition the design and distribution of loans to meet the needs of targeted customers. There are also conduct of business rules to know the customer, assess him and provide him clear and comprehensible information on the product by qualified staff. This chapter addresses the obligation to carry out the creditworthiness assessment of the potential borrower. The correct assessment requires to know the client, and to know the client it is necessary to assess him in a professional manner.