The need for novel and diverse sources of protein to feed the growing world population is urgent and stark. At the same time, peoples’ eating habits and values are also changing, with more consumers considering alternatives to traditional sources of protein. Novel protein sources not only need to provide essential amino acids and nutrition, but also cater to taste, convenience, cost economics, and personal needs. They also need to be ethically produced, with a smaller environmental footprint, and when feasible, closer to consumer. Insect protein has been researched intensively in recent years with promises to best fulfill these needs. As the insect protein field and industry are expanding and getting more mature at this stage, this review summarizes their properties and applications within the context of the food and feed industry. The important functional properties that make insect proteins useful are also discussed.