From time immemorial i t is well known that curtailment of freedom ofte n leads to changes in the behaviour of living beings. Similar restriction of freedom leads to selectivity in the chemical behavior molecules embedded i n biological systems. Extending these well - known concepts supramolecular chemists have established that even small molecules upon confinement in synthetic hosts exhibit behaviour distinctly different from the ones in an isotropic solution. In this lecture t he role a “Medium” in bri nging about changes in the well - established behaviour of excited molecules w ould be illustrated with select examples. Results of steady state and ultrafast experiments will be presented that highlight how the confinement alters the excited state dynamics of stilbenes and azobenzenes , the molecules that act as triggers in various biological systems and man - made devices . Another reaction to be discussed concerns with electron transfer (eT) that plays a fundamental role in a number of biological events including photosynthesis. Examples and ultrafast dynamics of donor s, imprisoned within an organic capsule, transfe r r ing an electron to an acceptor across a molecular wall would be presented . The main message of the talk is that molecules like humans behave differently when confined within synthetic cages .