Control of pests within public sector housing blocks attracted considered attention in the 1980s, and the concept of 'block control' then became established. Since that time there have been many changes in the provision of housing, and in the delivery of pest control. Nonetheless block control work against invasive pests has continued, and in addition 'new' pests such as bedbugs are also now involved. This article reviews the concept of block treatment, in a 21st century setting. Multi-unit housing blocks have been part of the urban landscape for many centuries, but the end of the Second World War saw a sudden demand for high volume, low cost housing. The approach developed by the architect Le Corbusier, for high density blocks, appeared to provide the answer. The boom time for the construction of public sector housing spanned 1950 to 1980, but subsided thereafter. Nonetheless by 1998, it was estimated that in Europe and the Russian Federation, 170 million people still lived in large housing estates (EAUE, 1998). Up until the 1980's, the majority of multi-unit housing blocks were managed by public sector organisations, but as a result of changes in politics and funding policy, there has been a gradual shift in the ownership of housing (Rust, 2008). Since the 1990s, another wave of housing block construction has taken place internationally, typically privately financed, that has been driven by high land prices and housing shortages. In contrast to the 1970s housing blocks, recent developments may be mixed function, incorporating shopping malls, restaurants and leisure facilities. Such facilities influence the pattern of infestation, and may complicate the responsibility for pest control.