Governments can help facilitate labour mobility and job searches through various interventions, including vocational training, as discussed above, and employment services, competency assessment programmes and skills certification (World Bank, 2010b). These policies can have the ancillary benefit of leading to increased knowledge spillover and faster technology transfer. Costs associated with a transition to a green economy, including unemployment arising from the shift from high-carbon industries, will need to be minimized through targeted measures such as worker retraining, potentially backed by international-level support through development assistance, including Aid for Trade. Green jobs need to entail decent work, with adequate wages, safe working conditions, job security and worker rights (United Nations Environment Programme, 2008).