The present book primarily deals with the lower rim substituted calix[4]arene derivatives and their metal ion complexes, and the biomimetic and biological studies of these complexes. Broadly, the book could be divided into the following three parts: (i) The K+ was found to act as template in the formation of calix[4]arene tetra-amide derivative exclusively, with the generation of calix[4]arene-monoanion and the structure of this has been characterized by single crystal XRD study. (ii) Metal ion complexes of p-tert-butylcalix[4]arene-diacid with Mn(II), Mn(IV), Fe(III), Co(II), Ni(II), Cu(II), Zn(II) and Sn(IV) have been discussed. Co-administration of lead and tin complexes on porphyrin metabolism, oxidative stress and distribution of metal ion concentration in blood and soft tissues in rats have been evaluated. (iii) Anthracene anchored derivatives of p-tert-butyl-calix[4]arene were subjected to the binding studies with the divalent metal ions. Based on the photo-physical studies, an imine-based derivative were found to act as a chemosensor for Fe(II)and Cu(II) ions.