RESPIRATORY diseases of pigs have undergone a variety of name changes over the years, partly as a reflection of the evolution of these diseases and partly as a result of changing fashions. From the point of view of the clinician who sees a pig with a cough or dyspnoea which fails to thrive, there is little difference clinically between a grower/finishing pig of the 21st century with porcine respiratory disease complex (PRDC) and a fattening (finishing) pig in the 1960s with enzootic pneumonia. The clinical signs are similar but the aetiology may be different due to changes in production methods, the development of efficacious vaccines and the appearance over the past decade or so of serious viral diseases affecting the respiratory tract. This article traces the evolution of porcine respiratory disease over recent decades, discusses the current disease priorities and briefly outlines strategies for control.