Despite the tremendous progress that has been made in macrocyclic chemistry since the discovery of corands, cryptands, and spherands more than four decades ago, macrocyclic systems possessing a high level of controllability in structural configuration concurrent with a systematic tunability in function are still very rare. Employing an inner design strategy to orient H-bonding forces toward a macrocyclic cavity interior while convergently aligning exchangeable ion-binding building blocks that dictate a near-identical backbone curvature, we demonstrate here a novel pentagonal framework that not only enables its variable interior cavity to be maintained at near-planarity but also allows its ion-binding potential to be highly tunable. The H-bonded macrocyclic pentamers thus produced have allowed a systematic and combinatorial evolution of ion-selective pentamers for preferential recognition of Cs(+), K(+), or Ag(+) ions.