Combining supramolecular principles with block copolymer self-assembly offers unique possibilitiesto create materials with responsive and/or tunable properties. The present chapter focuses on supramolecularmaterials based on hydrogen bonding and (block co-) polymers. Several cases will be discussed where theself-assembled nanostructured morphology can be easily tuned using composition as the natural variable.A large body of the material reviewed concerns hydrogen-bonded side-chain (block co-) polymers. Sidechains both with and without mesogenic units are discussed. Frequently the thermoreversibility of the hydrogenbonds allows for responsiveness of material properties to external stimuli such as temperature, pH, andelectromagnetic fields. Temperature-dependent photonic bandgap, temperature-dependent proton conductivity,pH-erasable multilayers, temperature-induced volume transitions, and fast AC electric field-induced orientationalswitching of microdomains are the main examples.