The discipline of paleoecologyaims to reconstructthe environmentin the past.This discipline is basedon the analysisand interpretation offossilfaunasandflorasin theirstratigraphicand geomorphologicalcontext.The obtainedknowledge of thepaleo-environmenthas provedindispensableto assessthe consequences of thecurrent environmentalchanges, includingthose of the climate.The objective ofthis course is to get familiar withthepaleo-ecological methodology.The resources that can be used by bothbotanicallyandzoologicallyorientedbiologiststo reconstruct the past environmentwill be discussed. A multidisciplinary approachis therefore of prime importance. The differentsteps requiredto bringapaleo-ecological study to a successful conclusionare discussed extensively such ascollectingsediment cores, the differentdatingtechniques used, andtheapplication ofgeochemical and biologicalproxies. Thislast partwill get most of the attention. The methodscoveredwill be furtherusedto showhowthe transition fromthe Pleistoceneto the Holocene, andalsothe further course ofthe Holocene, can be reconstructed. Anumber ofcase studieson various subjects, such astheacidificationof surface waters, the reconstruction of thechanges insea levelandice coverintheArctic Ocean, the impact ofNeolithic manonthe landscape, willillustrate this.