CONTENIDO: Development of a rationale for monitoring -- Scientific requirements of a monitoring programme -- Remote sensing techniques for monitoring land-cover -- Monitoring plant populations: census as an aid to conservation -- Vegetation monitoring -- Monitoring butterfly numbers -- Monitoring terrestrial breeding bird populations -- National species distribution surveys -- Monitoring at the county level -- Field monitoring: confessions of an addict -- Monitoring overseas: Prespa National Park, Greece -- The calculation of index numbers from wildlife monitoring data -- Biological monitoring and ecological prediction: from nature reserve management to national state of the environment indicators.