 Although some agencies in some areas, such as the US state of Minnesota, allow winter service vehicle drivers to operate without any extra training, most provide supplemental lessons to drivers to teach them the most effective and safe methods of snow removal.Many require that trainee drivers ride-along with more experienced drivers, and some even operate specially designed driving simulators, which can safely replicate dangerous winter driving conditions.Other organisations require that all staff have a recognised additional licence or certificate—the United Kingdom Highways Agency for example requires that all staff have both a City & Guilds qualification and a supplemental Winter Maintenance Licence.