Many instrumentation engineers and scientists often deal with analog electronic issues when approaching delicate measurements. Even if off-the-shelf measuring solutions exist, comprehension of the analog behavior of the measuring system is often a necessity. This book provides a concise introduction to the main elements of a low frequency analog acquisition chain. It aims to be sufficiently general to provide an introduction, yet specific enough to guide the reader through some classical problems that may be encountered in the subject. Topics include sensors, conditioning circuits, differential and instrumentation amplifiers, active filters (mainly for anti-aliasing purposes) and analog to digital converters. A chapter is devoted to an introduction to noise and electronic compatibility.