In terms of merciless competition, the complex requirements of customers/ users and complex products/services, the importance of gaining personal sales as an instrument of promotional mix rises. In these new circumstances, sales are no longer based on the manipulation, but on providing information, solving specific problems and bargaining. The development philosophy of personal selling involves three basic assumptions: the acceptance of marketing ideas, sales and evaluation of personal selling and taking up the role of the one who offers a solution to the problem and thus becomes a partner with the customer. As an imperative goal for providers of goods and services in today's market imposes on the strategic and consultative sales with added value (range of creative improvements in the sales process that deepens the customers' experience). The seller creates added value by being in the sales conversation with a customer establishing of trust (based on two-way communication), carefully discovering their needs and offering superior solutions. The model of strategic-advisory sales development includes five steps: personal sales philosophy, a strategy for establishing relations, product strategy, the strategy of winning over customers and strategy presentations. By applying strategic and advisory model, the performance of economic entities operating on the territory of Serbia can be improved in a relatively short period of time (with minimal investment). Consequently, the competitiveness of the entire economy is also improved.