With over 50 million PROFIBUS field bus nodes in operation, PROFIBUS DP is by far the most popular with continuing growth. However, as the number of new DP network installations keep rising, so do their application specific requirements. Amongst these are higher operating temperatures and isolation voltages, as well as smaller form factors. This paper describes best practices for new designs of PROFIBUS DP nodes, and covers bus node isolation, PROFIBUS compliance, and bus signal polarity.