It is estimated that 1.3 billion people currently smoke cigarettes or other tobacco products. Smoking is becoming an epidemic worldwide and is a major risk factor for atherosclerosis and heart disease. Research has shown that smoking causes changes in platelet membrane fluidity and Na(+)/K(+)ATPase activity. The aim of the current research is to determine if these changes in membrane fluidity are ultrastructurally visible. Thirty-five experimental and control subjects were selected for the study. Smokers had smoked on average 2 cigarettes per day for 5-10 years. Smears of platelet-rich plasma were prepared for scanning electron microscopy and viewed with a Zeiss ULTRA plus FEG-SEM with InLens capabilities. Platelet surface morphology was viewed at 1 kV and micrographs were taken at 80,000-200,000× machine magnification. A difference in the globular nature of the platelet membrane of smokers was visible; additionally, it seemed as if surface pseudopodia were more pronounced than in healthy individuals. No apoptotic or necrotic platelet morphology was noted. Research has noted changed membrane fluidity and the study concludes by suggesting that this is visible ultrastructurally. Therefore, changes in membrane fluidity are structurally visible and translate into a more globular and bulbous appearance of the membrane surface.