It would depend on the culture and prior history of the ORGANIZATION, as WELL as the NATURE and source of the demand for software quality, but I have usually found it easier to get started with walkthroughs.
In some cases, there is already a formal (but lapsed) procedure mandating either walkthroughs or inspections. In such cases, the first task is to unpick the reasons why the previous attempts have FAILED. Typically, past inspections have inspected the wrong things at the wrong times, using the wrong criteria at the wrong level of detail.

It would depend on the culture and prior history of the organization, as well as the nature and source of the demand for software quality, but I have usually found it easier to get started with walkthroughs.
In some cases, there is already a formal (but lapsed) procedure mandating either walkthroughs or inspections. In such cases, the first task is to unpick the reasons why the previous attempts have failed. Typically, past inspections have inspected the wrong things at the wrong times, using the wrong criteria at the wrong level of detail.