TPRM maturity levels can be aligned to the NIST Cyber Security Maturity Model with 5 levels (Initial-L1 to Optimal-L5), the CMMC model by the DoD, or any other globally recognized standard. This will be an eye-opener, as we take pride in the way we manage to get to do things with the bare minimum of escalations. But this realization is paramount for organizations that take third-party risk seriously. A typical maturity model needs to be carefully crafted by considering (but not limited to) all the key components of the program, key security domains, the TPRM roadmap, resources (all types), the governance model, and compliance with legal and regulatory requirements. Define criteria for each of the levels and set the baseline that will help you categorize the input criteria. Define compliance levels against each of the criteria (e.g., compliant, non-compliant, or partially compliant).
Note: A pre-requisite for a solid maturity model is to ensure your TPRM program has all the essential components and is well-defined and configured.
This will get the ball rolling, and you will come up with many questions for which you will start seeking answers, and that’s how the journey will begin. If you cannot do it by yourself, seek assistance within or outside your organization from consultants to help you build the TPRM program and maturity model.