Auscultation of the lungs with a stethoscope is an important and simple diagnostic method. It gives direct information about the structure (and function) of lung tissue that cannot be gathered by any other simple and non-invasive method. Changes in the quality of lung sounds are often directly correlated to pathological changes in the lungs. Particularly in practical medicine, auscultation is very important and considered a standard method of diagnosing and monitoring pulmonary diseases alongside lung function testing and chest x-rays. The multiplicity of lung sounds that can be observed makes it difficult even for a physician to arrive at a definite diagnosis. Today, auscultation sounds are divided into two main groups, respiratory sounds and rales. Both respiratory sounds and rales contain important diagnostic information. Respiratory sounds include vesicular breathing, trachea air-flow sounds, and bronchial breathing. Rales include moist and dry rales, crackling, crepitation, rhonchus, and wheezing. The small selection of lung sounds mentioned above gives an idea of the difficulty of making a clear diagnosis. In a current research project run jointly by Joanneum Research and the Pulmonary Day Care Center at the LKH-Graz-West hospital in Graz it is intended to develop a system similar to medical expert system to help the general practitioner or specialist diagnose lung diseases quickly and clearly. The objective of the first steps of the research project is to lay the foundation by developing new sensors and the recording software an to make extensive physicals.