Novel processes for the preparation of thieno[2,3-b]pyridine derivatives which are substituted in the 2-position by a substituted anilino moiety and intermediates thereto are provided. The compounds prepared by the present processes may be useful, for example, as selective inhibitors of human MEK (MAPKK) enzymes, and are accordingly of benefit in medicine, for example in the treatment of inflammatory, autoimmune, cardiovascular, proliferative (including oncological) and nociceptive conditions. The present processes may offer improved yields, chemical or stereochemical purity, ease of preparation and/or isolation of intermediates and final product, and more industrially useful reaction conditions and workability.