Molecular gels of cetylpyridinium chloride (CPC) in binary solvent mixtures have been investigated. CPC formed a turbid gel at a critical solvent composition of 3:1 v/v CHCl 3:H 2O. The gelation ability was evaluated in various other organic solvents in the presence of water and the phase evolution was studied. The microstructure of the CPC gel was proposed based on spectroscopic, microscopic and small-angle X-ray scattering (SAXS) techniques. A detailed molecular level investigation using SAXS and molecular modelling demonstrated the gel to assemble as a lamellar organization maintaining a highly interdigitated bilayer structure with CPC molecules. Concentration dependent hierarchical self-assembly from micelles to fibrous gels was thus elucidated with highly interdigitated lamellar gel organization resulting from intense hydrophobic interactions in the tail-to-tail arranged bilayers. The stimuli responsiveness of the gel was elucidated with pH dependent entrapment of Congo Red. © 2012 The Royal Society of Chemistry.