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The relevance of urea is wide ranging, both as a molecule involved in animal (also human) metabolism, and as being responsible for breaking the paradigm that organic molecules can only be synthesised biologically. It is, therefore, an interesting target in extraterrestrial searches for building blocks of life (as we know it). Following several attempts, urea was successfully detected in a broadband ALMA survey of Sagittarius B2 interstellar molecular cloud (A&A 2019, 628, A10). Investigation of the rotational spectrum of urea that was used for astrophysical detection is not convenient and dates back to 1975. Understanding of the lowest vibrational energy levels has also been particularly challenging even though many studies of the infrared spectrum have been published. The most comprehensive study of the rotational spectrum of urea was only completed recently (J. Mol. Spectrosc. 2022, 390, 111706). The pattern of low lying vibrational levels has been established unambiguously, posing a challenge to quantum chemistry computations. An overview of both laboratory and astrophysical studies will be presented.