This technical paper describes experience, lessons learned and best practices in conducting reviews of various arrangements under the Convention and the Kyoto Protocol. It looks at experience from the reviews of 10 such arrangements, including constituted bodies, frameworks and mechanisms, and identifies common elements that, by extrapolation, may in some cases be considered best practices for future reviews. Bringing those elements together, it may be noted that the Conference of the Parties (COP) generally undertakes the review, with the support of the Subsidiary Body for Implementation (SBI). In addition, the secretariat often prepares official documents to support the process. Frequently the review is qualitative, drawing on inputs from Parties and observer organizations and reports of bodies. In some cases, terms of reference are prepared, with sections on the review’s scope, methodology, principles or criteria. On average a review takes one year to complete and is undertaken every four years. Finally, the review generally results in a COP decision. The SBI may consider the findings contained in this report as it continues to elaborate the scope of and modalities for the periodic assessment of the Technology Mechanism.