This project has three objectives: O1) to develop and test the feasibility and acceptability of a 8-week VR ACT program (VR-ACT) in a sample of CPSP patients; O2) to pilot test the efficacy of VR-ACT in improving pain, mental health, and adaptive psychological processes and skills, and in reducing the functional connectivity of the Triple Network (DMN, SN, and FPN); O3) To examine the cost-effectiveness of the VR-ACT. The current project will conduct a parallel group design Randomized Controlled Trial (RCT) and will follow a multi-method approach (qualitative and quantitative assessment).