Background: Rigorous verification and validation practices are regarded essential for successful implementation of Integrated Computational Materials Engineering (ICME) for aerospace applications. Guidelines and a recommended best practice for ICME verification and validation were developed in 2011 under Air Force Research Laboratory sponsorship and were published in 2012. These included general guidelines for ICME verification and validation, a recommended best practice, practitioner aides in the form of checklists for planning and status assessment, a Tool Maturity Level assessment guide, and a recommended approach for risk vs. consequence assessment for specific ICME applications. ICME development programs and expert practitioners have since reviewed and used the guidelines and provided constructive feedback for improvements. Findings: This feedback was used to generate a comprehensive revision to the original guidelines and recommended best practice, as well as to the corresponding practitioner aides. The System-Level and Model-Level Checklists were simplified and improved, as was the Tool Maturity Level assessment guide. A template for a one-page summary chart was also generated to facilitate communication of status. Conclusions: Experience with several ICME-related programs and expert practitioners reinforced the conclusion that guidelines and a recommended best practice are important tools to ensure that rigorous, comprehensive verification and validation practices are employed during ICME development and implementation efforts.