Continued improvement of performance has become a real challenge for most companies and organization. This paper presents a framework using Fuzzy Cognitive Maps (FCM) method to quantitatively analyze the influence and relationship among the KPIs used to monitor performance. The proposed method can help the top management and decision-makers to identify the improvement behavior of one Key Performance Indicator (KPI) target on the other KPIs and in the Performance Management System (PMS) as whole. A different scenario was conducted in one of the engineering organizations to analyze the interconnections between the KPIs and the impact of changing the targets. Fuzzy Cognitive Maps have been fruitfully used in decision making and simulation of complex PMS and help the management in order to adjust targets of performance. Key word: KPIs; fuzzy cognitive maps; PMS; trade-off.