A modular implant includes a head, an intermediate part configured to engage bone, and an initially separate anchor configured to engage the head so that at least the head and the anchor cooperatively secure the intermediate part on the implant to form the modular implant. At least one of the head, the intermediate part, and the anchor has a plurality of forms, and each form is configured to be assembled on at least one form of the other two of the head, intermediate part, and anchor. The intermediate part may include a porous metal such as tantalum.