Against the backdrop of the environmental setting of the subequatorial NE Pacific abyssal plain, the book will characterise the meiobenthos as an ecological category in the deep sea and introduce research lines meiobenthic studies are applied to, including environmental assessments of human-induced disturbance of the deep seafloor. It will proceed to present an overview of the current knowledge on the meiobenthos of the area of concern and will discuss general considerations regarding the use of meiobenthos as indicator of seafloor disturbance. It will address the question of deep-sea mineral resources development versus benthic communities and will present an overview of field studies ("experiments") aimed at assessing the magnitude of potential impact associated with seafloor resources development (polymetallic nodule mining in particular) in the Pacific.