Background: The Synergy system implementation is a novel language founded on eight universal characteristics: predictability, complexity, stability, vulnerability, resilience, and involvement in decision-making and caregiving. Aim: To evaluate the effectiveness of synergies system implementation on staff nurses' competency, performance, and patient satisfaction. Study design: A quasi-experimental research design was used to achieve the aim of the current research. Setting: The study was conducted in the Critical Care Unit at South Valley University Hospital. Subject: A convenience sample of Staff Nurses (N= 50) working in the previously selected setting and this study included 50 patients. Tools: Three tools were used for data collection: Tool (I) Synergies System Scale which consisted of two parts; Part (I) Nurses' data and Part (II) Nursing Competency Scale; Tool (II) Patients' demographic data; and Tool (III): Patient' Satisfaction assessment tool. Results: The study revealed that staff nurses had an unsatisfactory knowledge level in pre-synergies system implementation but satisfactory in post-synergies system implementation (76%) with a statistically significant relation. Also, most patients reported their satisfaction with nurses' communication & nurses' skills and competencies. Conclusion: Synergies system implementation positively affects staff nurses' competency, performance, and patient satisfaction. Recommendation: Continuous training about the synergies system for all nurses is recommended to be applied. Replication of the current study with a larger sample of nurses in different settings is required to generalize the results.