During the last years the use of intelligent strategies for tuning Proportional-Integral-Derivative (PID) controllers has been growing. The evolutionary strategies have won an important place thanks to their flexibility. In this paper, the automatic tuning of systems with stable and unstable dynamics, through a genetic approach is presented. The advantages of the proposed approach ere highlighted through the comparison with the Ziegler-Nichols modified closed loop method, and the Visioli genetic approach. The proposed methodology goal is to expand the intelligent tuning application to a wider range of processes (covering systems with oscillatory or unstable modes).