A retention system for footwear, the retention system comprising: opposed constrictors (23b, 23b') and a tensioner configured to urge the opposed constrictors (23b, 23b') toward each other in response to a tensile force applied to the tensioner; opposed first and second anchors spaced from the tensioner; a retainer having opposed first and second retainer couplers (22a, 22b), wherein the first retainer coupler operatively engages the first anchor and the second retainer coupler operatively engages the second anchor such that a tensile load applied to one or both of the first and second retainer couplers (22a, 22b) urges the retainer toward one or both of the first and second anchors, wherein each of the first retainer coupler and the second retainer coupler is operatively engaged with the tensioner such that a tensile load applied to the tensioner urges the first retainer coupler and the second retainer coupler into tension and thereby urges the retainer toward one or both of the first and second anchors, and wherein: the opposed first and second anchors comprise respective first and second apertured members; the retainer comprises a portion of a tongue member and the opposed first and second retainer couplers (22a, 22b) comprise respective first and second strap segments outwardly extending from the tongue member and through the apertured members; and the operative engagement between the first retainer coupler and the tensioner comprises a first slidable engagement of the first strap segment with the tensioner, and the operative engagement between the second retainer coupler and the tensioner comprises a second slidable engagement of the second strap segment with the tensioner. opposed constrictors (23b, 23b') and a tensioner configured to urge the opposed constrictors (23b, 23b') toward each other in response to a tensile force applied to the tensioner; opposed first and second anchors spaced from the tensioner; a retainer having opposed first and second retainer couplers (22a, 22b), wherein the first retainer coupler operatively engages the first anchor and the second retainer coupler operatively engages the second anchor such that a tensile load applied to one or both of the first and second retainer couplers (22a, 22b) urges the retainer toward one or both of the first and second anchors, wherein each of the first retainer coupler and the second retainer coupler is operatively engaged with the tensioner such that a tensile load applied to the tensioner urges the first retainer coupler and the second retainer coupler into tension and thereby urges the retainer toward one or both of the first and second anchors, and wherein: the opposed first and second anchors comprise respective first and second apertured members; the retainer comprises a portion of a tongue member and the opposed first and second retainer couplers (22a, 22b) comprise respective first and second strap segments outwardly extending from the tongue member and through the apertured members; and the operative engagement between the first retainer coupler and the tensioner comprises a first slidable engagement of the first strap segment with the tensioner, and the operative engagement between the second retainer coupler and the tensioner comprises a second slidable engagement of the second strap segment with the tensioner. the opposed first and second anchors comprise respective first and second apertured members; the retainer comprises a portion of a tongue member and the opposed first and second retainer couplers (22a, 22b) comprise respective first and second strap segments outwardly extending from the tongue member and through the apertured members; and the operative engagement between the first retainer coupler and the tensioner comprises a first slidable engagement of the first strap segment with the tensioner, and the operative engagement between the second retainer coupler and the tensioner comprises a second slidable engagement of the second strap segment with the tensioner.