Nanodiscs are disc-like structures formed by two copies of a membrane scaffold protein, engineered from apolipoprotein A-I, surrounding a phospholipid mixture that can incorporate membrane proteins preserving their natural properties. They behave as soluble entities allowing the use of high-resolution structural techniques to determine the structural organization of the embedded membrane protein, and the use of solution biochemical-biophysical tools to measure its activity, assembly and interactions with other proteins in membranelike environments. In addition, nanodiscs are biocompatible which makes them an attractive technology to be used in therapy, drug discovery, and other biotechnological applications.