In this thesis, the most commonly studied crystalline sponge [{(ZnI2)3(tris(4-pyridyl)-1,3,5-triazine)2·x(CHCl3)}n] (1) was used to produce three novel complexes. The structure of three terpenes namely farnesol, geraniol and β-damascone were determined in the pores of sponge 1. Despite being the most successful crystalline sponge 1, has a few limitations such as exhibiting a hydrophobic pore environment, small pore size and instability in the presence of polar solvents and nucleophiles. Literature MOFs were searched for alternative crystalline sponges to overcome these limitations. The MOF {[Co2(L)(H2O)3]·(solvent)x}n L = bis-(3,5-dicarboxy-pheny1)terephthalamide (3) was investigated as an alternative crystalline sponge and studies resulted in two novel complexes with 3-phenylpropanol and 2-phenylethanol. In sponge 3 guest binding occurred via hydrogen bonding and the hydrophilic pore environment was suitable to accommodate polar solvents. Another literature MOF {[Cd7(BTA)4(H2O)(DMF)]·(solvent)x}n BTA = 4,4’4’’-[1,3,5-benzenetriyltris(carbonylimino)]-trisbenzoic acid (4) was also investigated as an alternative crystalline sponge. Due to different synthetic procedures being used, a new structure of the MOF 4 was developed and that was used in subsequent studies. Sponge 4 outperformed sponge 1 in terms of stability and was stable in the presence of polar aprotic, polar protic solvents and Lewis bases. Inclusion complexes with the solvents, acetonitrile, acetone, and isopropanol demonstrated a hydrophilic pore environment where these guest molecules were fixed via hydrogen bonding. In contrast, pyridine was accommodated in sponge 4 via the coordinative alignment method (CAL). This observation led to the generation of five novel inclusion complexes with 4-aminopyridine, 3,5-lutidine, 3-bromopyridine, 4-acetylpyridine and 4,4’-bipyridine, which were accommodated in 4 via CAL. Another investigation was made to compare the closely similar structures of sponge 4 and pyridine derived sponge 4’. N,N-dimethylaniline and propiophenone were accommodated in the pores of both the sponges and the differences in the host-guest interactions were studied. In the inclusion complexes of 4 and 4’ with N,N-dimethylaniline hydrogen bonding was not observed as the dominant host-guest interaction.