Abstract: A passive-adaptive indentor is provided for cold working a material that includes a material surface and a depth extending in a direction that is perpendicular to a direction of the material surface. The passive-adaptive indentor has a first member that includes a first working end that is configured to create a first residual stress field that extends to a predetermined depth in the material. The passive-adaptive indentor also has a second member that includes a second working end that is configured to create a second residual stress field that extends to a generally fixed second depth of the material regardless of the depth to which the first residual stress field extends. A method of using a passive-adaptive indentor for cold working a material is also presented.