In 1997 Europe's tallest skyscraper was inaugurated in the centre of Frankfurt to serve as the headquarters of a major German bank. Beyond its technical innovations, this building also marked a major step in the urban policy field: it was the first skyscraper constructed to comply with ecological conditions. These conditions represented the outcome of a long decision-making process, involving the bank's directors, local politicians and utility managers. After years of negotiations, they became the basis of a covenant signed by the bank and Frankfurt's urban planning department.