The concept of configurational (material) force has been introduced by Eshelby to describe the motion of massless (voids, microcracks, vacancies, or dislocations) or heavy (inclusions) defects within a solid body as the result of mechanical or thermal loading. This concept has been exploited through the years for modelling the crack-driving force in fracture mechanics, the Peach–Koehler force of dislocations, or the material force developing on a phase boundary in a solid under loading. In the present work, the action of configurational forces on elastic structures are theoretically and experimentally proven in the presence of a specific movable constraint: a frictionless, perfectly smooth and bilateral sliding sleeve. Intriguing mechanical behaviours are disclosed for compliant structural systems involving configurational constraints. The following cases will be examined: (i) An elastic rod constrained by a frictionless sliding sleeve ending with a linear spring and subject to a dead load at the other end, (ii) The sudden release of a rod with a concentrated weight attached at one end and partially inserted into a frictionless sliding sleeve at the other and (iii) The periodic oscillation of a configurational constraint during the fall of a rod. The results represent innovative concepts in mechanics to be used in advanced applications, as for example in actuation mechanisms, energy harvesting, vibration mitigation, shock absorbers.