This article is the culmination of several decades of work on the land snail fauna of Sabah, Malaysian Borneo. In it, the fauna for several problematic land snail genera is revised, namely Acmella and Anaglyphula (Caenogastropoda: Assimineidae), Ditropopsis (Caenogastropoda: Cyclophoridae), Microcystina (Pulmonata: Ariophantidae), Philalankaand Thysanota (Pulmonata: Endodontidae), Kaliella and Rahula, (Pulmonata: Euconulidae), and Trochomorpha andGeotrochus (Pulmonata: Trochomorphidae). In addition, new species are added to previously revised genera, such as Diplommatina (Diplommatinidae) and Georissa (Hydrocenidae), as well as some new species of genera not revised previously, such as Japonia (Cyclophoridae), Durgella and Dyakia (Ariophantidae), Amphidromus and Trachia(Camaenidae), Paralaoma (Punctidae), and Curvella (Subulinidae). We distinguish 48 new species, and re-describe a further 31. Since most species were collected with techniques that are aimed at gathering empty shells, the descriptions are based on conchology only. It is hoped that this paper will generate renewed interest in the rich snail fauna of this region, an will serve as a basis for further anatomical, evolutionary, and ecological studies.