This invention relates to a process for preparing amido-carboxylic acids in water. The process involves four steps. Step (A) involves hydrolyzing a lactam at a temperature of 150 °C - 300 °C to form a mixture containing an amino acid. Step (B) involves cooling the reaction mixture formed in step (A) to a temperature of 25 °C - 100 °C. Step (C) involves reacting a carboxylic acid anhydride with the amino acid formed in step (A) to form a reaction mixture containing an organic layer which contains an amido-carboxylic acid and an aqueous layer. Step (D) involves separating the amido-carboxylic acid containing organic layer from the aqueous layer. The presence of water aids in product isolation by phase separation and recycle of the reactants. Amido-carboxylic acids are used to make bleach activators for detergents.