These guidelines are intended to assist the project design team, Project Archaeologist, archaeological consultants and contractors working on archaeological testing, field survey, excavation and post-excavation phases of archaeological mitigation in wetlands on national road schemes. Further guidelines relating to the initial planning and Environmental Impact Statement (EIS) preparation, some pertaining to wetlands, are presented in Guidelines for the Assessment of Archaeological Heritage Impact of National Road Schemes (National Roads Authority 2005). Wetlands can be defined as "any area of land covered by water for part of each year, or each day, or which has been drowned by water at any time of its existence" (Coles 1984), or in which a high water table is the dominant feature in determining the ecological status of a landscape. For the purposes of these guidelines this definition encompasses a wide range of wetland environments, including peatlands, rivers, lakes (current and former), estuaries, seasonally flooded areas (such as callows or turloughs) and coastal areas. (This document does not address underwater areas where archaeological diving methodologies apply.) Many of the provisions of these guidelines are also relevant to waterlogged material on dryland sites, such as basal deposits in ditches and pits.