This critical review examines transition metal-catalyzed decarboxylative couplings, which have emerged as a powerful strategy for forming carbon–carbon or carbon–heteroatom bonds from carboxylic acids. These reactions involve the cleavage of C-C bonds to carboxylate groups and the formation of new carbon-carbon bonds. Decarboxylative cross-couplings offer advantages over traditional cross-coupling or addition reactions involving preformed organometallic reagents. The review focuses on decarboxylative coupling reactions, particularly decarboxylative cross-coupling reactions, which have gained prominence in recent years following the discovery of decarboxylative Heck-type reactions and decarboxylative biaryl syntheses. The key step in these reactions is the decarboxylation of carboxylic acids, which can be promoted by various catalyst systems. The review discusses the decarboxylation step, including protodecarboxylation and oxidative decarboxylation, and explores the application of these reactions in the synthesis of biaryls, ketones, azomethines, arenecarboxylate esters, azaarenes, alkynes, and α-amino acids. It also highlights the decarboxylative coupling with boronic acids and the decarboxylative Heck reaction. The review emphasizes the advantages of decarboxylative couplings, such as the use of readily available carboxylic acids and the formation of valuable products through multifaceted reaction pathways.This critical review examines transition metal-catalyzed decarboxylative couplings, which have emerged as a powerful strategy for forming carbon–carbon or carbon–heteroatom bonds from carboxylic acids. These reactions involve the cleavage of C-C bonds to carboxylate groups and the formation of new carbon-carbon bonds. Decarboxylative cross-couplings offer advantages over traditional cross-coupling or addition reactions involving preformed organometallic reagents. The review focuses on decarboxylative coupling reactions, particularly decarboxylative cross-coupling reactions, which have gained prominence in recent years following the discovery of decarboxylative Heck-type reactions and decarboxylative biaryl syntheses. The key step in these reactions is the decarboxylation of carboxylic acids, which can be promoted by various catalyst systems. The review discusses the decarboxylation step, including protodecarboxylation and oxidative decarboxylation, and explores the application of these reactions in the synthesis of biaryls, ketones, azomethines, arenecarboxylate esters, azaarenes, alkynes, and α-amino acids. It also highlights the decarboxylative coupling with boronic acids and the decarboxylative Heck reaction. The review emphasizes the advantages of decarboxylative couplings, such as the use of readily available carboxylic acids and the formation of valuable products through multifaceted reaction pathways.