An animal containment fence for containing an animal upon an impact from the animal when the impact applies less force than a release force for preventing injury to the animal upon impacting the fence, the fence comprising: at least two posts, each post of the at least two posts comprising a bottom end for anchoring to a surface and a top end for projecting away from the surface; at least two connection members, each connection member of the at least two connection members being transversely coupled to a respective post of the at least two posts and comprising an oblong shape and two ends; at least two connectors, each connector of the at least two connectors passing laterally through a respective connection member of the at least two connection members at positions outside the at least two posts; at least one cross-member, the at least one cross-member comprising opposite ends, each of the opposite ends being in a telescopic engagement with one end of the two ends of two connection members transversely coupled to a respective post of the at least two posts to permit telescopic movement between the at least one flexible cross-member and the at least two connection members; characterized in that the fence comprises at least one cross-member which is flexible and constructed from at least one elastic, polymeric material, and the telescopic engagement is configured to move reciprocally upon a flexion of the at least one flexible cross-member caused by an applied force less than a release force, and to release upon a flexion of the at least one flexible cross-member caused by an applied force equal to or greater than the release force by shortening the distance between the opposite ends of the at least one flexible cross-member by an amount resulting in release of telescopic engagement of at least one of the opposite ends of the at least one flexible cross-member with one end of the two ends of two connection member. at least two posts, each post of the at least two posts comprising a bottom end for anchoring to a surface and a top end for projecting away from the surface; at least two connection members, each connection member of the at least two connection members being transversely coupled to a respective post of the at least two posts and comprising an oblong shape and two ends; at least two connectors, each connector of the at least two connectors passing laterally through a respective connection member of the at least two connection members at positions outside the at least two posts; at least one cross-member, the at least one cross-member comprising opposite ends, each of the opposite ends being in a telescopic engagement with one end of the two ends of two connection members transversely coupled to a respective post of the at least two posts to permit telescopic movement between the at least one flexible cross-member and the at least two connection members; characterized in that the fence comprises at least one cross-member which is flexible and constructed from at least one elastic, polymeric material, and the telescopic engagement is configured to move reciprocally upon a flexion of the at least one flexible cross-member caused by an applied force less than a release force, and to release upon a flexion of the at least one flexible cross-member caused by an applied force equal to or greater than the release force by shortening the distance between the opposite ends of the at least one flexible cross-member by an amount resulting in release of telescopic engagement of at least one of the opposite ends of the at least one flexible cross-member with one end of the two ends of two connection member.