The Betrothal of January (Finnish: tammikuun kihlaus) was a declaration given by the that recognized the trade unions and their central organization the Finnish Federation of Trade Unions (SAK) as parties in collective bargaining on questions of industrial relations. The two sides agreed that they would start trying to reach a common understanding for further negotiation. The declaration was read on the evening news bulletin of the public service radio Yle on 23 January 1940 and published in newspapers the following day. Until then, only printers had collective agreements on their working conditions.