This book describes the design, synthesis and characterization of a series of novel metal-organic frameworks constructed amide and oxamide functionalized carboxylate ligands. Gas sorption applications of these porous materials have been studied, with an emphasis on CO2 storage. Extended metal-organic structures exhibiting large surface areas and high total pore volumes are favourable for CO2 uptake at low and high pressures. The strategies to enhance CO2 adsorption in MOFs are discussed.