ABSTRACT: Objectives: Dysphagia occurs in approximately 51%–78% of patients with acute stroke. The incidence of pneumonia caused by aspiration in dysphagic patients increases both mortality and the need for hospitalization. The aim of this study was to investigate whether the incidence of aspiration pneumonia could be reduced in such patients by an early screening for dysphagia and intensified oral hygiene. Material and Methods: In this controlled trial, 146 hospitalized acute stroke patients with moderate or severe dysphagia were included in three groups: an intervention group (n = 58), one internal control group (n = 58, retrospectively selected from same clinic), and one external control group (n = 30) from a comparable stroke unit in a neighboring hospital. The intervention consisted of early screening with a clinical method of dysphagia screening, the Gugging Swallowing Screen, and intensified oral hygiene. Results: The incidence of x-ray verified pneumonia was 4 of 58 (7%) in the intervention group compared with 16 of 58 (28%) in the internal control group (p < .01) and with 8 of 30 (27%) in the external control group (p < .05). Conclusions: Early and systematic dysphagia screening by the Gugging Swallowing Screen method and intensified oral hygiene reduced the incidence of x-ray verified pneumonia.