Biographical Sketch: Mark Zelden, Software Engineer Sr. Principal Leader Mark Zelden is an accomplished senior systems programmer and z/OS team lead for CSC (Computer Sciences Corporation) and a consultant with over 25 years of experience providing solutions for corporate IT organizations. Mark is ITIL V3 certifed and is an industry recognized leader in the MVS-OS/390-z/OS operating environment. He has a successful track record as a consultant and systems programmer with expertise in operating systems, Parallel Sysplex, security software, (RACF, Top Secret, ACF2), JES2, SMP/E, Workload Manager (WLM), networking (VTAM / NCP / TCPIP), DASD management, system software installation and support - including dozens of ISV software products, and technical applications support. Mark also has expertise in mainframe performance and tuning, capacity planning, technology strategy and planning, and problem diagnosis/resolution. His positions have required both independent, hands-on involvement and project leadership / management, and his strengths include a solid technical foundation coupled with strong people and interpersonal skills. Mark has authored utility programs that have been included on the CBT tape, his own web site, Mark's MVS Utilities, that is one of the most recommended sites in the industry, and articles for publications like Xephon's MVS Update magazine, TSO Times, and IBM Systems Magazine. Mark is the Systems Programming expert on the panel of S/390 experts for the "Ask The Experts" feature of search390.com and the TechTarget Expert Answer Center for OS/390 and z/OS operating systems. Mark and his web site have been featured in SHARE presentations over the years (most recently in the spring 2010 "Cheryl’s Hot Flashes" session from Seattle and the summer 2009 "Fully Wired System Programmer" session from Denver) and in industry publications including Cheryl Watson's Tuning Letter (2010 No. 1) and the January / February 2008 issue of IBM Systems Magazine in an article called "The Legend of Zelden".