Dan Krygowski, with The Discovery Group in Denver, CO, has over 30 years of experience in the art and science of petrophysics, and in the design and development of petrophysical software. During much of that time he has also taught courses in basic petrophysical interpretive methods. Dan earned M.S. and Ph.D. degrees in geophysics (with a focus on petrophysics) from the Colorado School of Mines. He worked for Cities Service Company, ARCO, Landmark Graphics, and Chevron prior to joining The Discovery Group in late 2006. He is the co-author, with George Asquith, Steven Henderson, and Neil Hurley, of Basic Well Log Analysis, Second Edition, published in 2004 by AAPG. He is a member of SPWLA, AAPG, SPE, SEG, RMAG and the Denver Well Logging Society. He is a Texas Registered Professional Geoscientist.