The construction industry deals with the provision of shelter and infrastructure for acontinuing growing population and urbanization, especially in developing countries, Thissector is well known as a huge consumer of natural resources; which produces a significantquantity of construction and demolition waste, Data about the situation of construction wastegeneration in Costa Rica is scarce and the objectives of the study were to develop a baselinestudy to determine quantities and composition of the waste, as well as, motivators and barriersfor achieving a more sustainable activity, This paper draws the findings of the surveyundertaken by means of questionnaires, interviews and site visits, The composition basicallyis wood, soil, piping materials, corrugated roof sheets, wires, packaging materials (paper,plastic and cardboard), cement, concrete, blocks, paints and debris, The amounts (either byvolume or by weight) of these streams are unknown since the majority of the companies don'tkeep track of these data, It is suggested a value of I 00 kg/m2 as an educated guess of theamount of construction waste produced, This high amount, compared to lower values found inliterature for developed countries, could be explained by the general lack of awareness andinformation on environmental issues as well as lack of technologies, governmentalenforcement and market incentives to improve the environmental footprint of the sector,