Dulce de leche [milk caramel] is one of the most exquisite milk derivatives with particular color, taste, and consistency that differentiate it from other dairy products. These attributes are developed during the manufacturing process through nonenzymatic browning reactions (Maillard reaction and caramelization), where the Maillard reaction is the main responsible. The heating processing (at temperatures above 100 °C) and concentrating milk with ingredients, especially sucrose (partially or not substituted by monosaccharides) and pH regulation, favors these reactions. The gelation of milk proteins also occurs and partially causes the development of the dulce de leche texture where the Maillard reaction would be affecting it by cross-linking reactions. Various processing variables are involved in the manufacturing of dulce de leche, such as temperature, type and concentration of carbohydrates, type, and concentration of amino acids, time, pH, water activity, and metal cations. There are many varieties of dulce de leche, such as familiar [classic or homestyle], repostero [for baking], pastelero [for patisserie], or heladero [for ice-cream making]. The above has led to different manufacturing processes and formulations, with modifications depending on the country and the selected methodology, which also depends on the production volumes, the company’s investment capacity, the costs, and the desired profit. Besides similarities among the manufacturing protocols, significant disparities exist as well and this chapter intends to clarify and to relate them to the distinctive attributes of the several styles of dulces de leche.