Saunderson is one of the most respected names in women's football, having won the WPL Southern Division title with the Cottagers in 2008, before taking a sabbatical from the game after the birth of his daughter.
"I was lucky to be approached by a number of clubs but once West Ham made their interest known, it was an easy choice," Saunderson told shekicks.net.
"I am sure it will be a challenge at times but I see the potential and passion in the club and that is what makes it such an exciting proposition."
Following the club's end-of-season AGM, previous manager Julia Setford has moved upstairs into a Director of Football capacity, as well as assisting Saunderson.
"Basically, we have had a little change," Setford told whufc.com.
"Mark is going to be first team manager and I will be his number two and also fill the role of Director of Football. The changes will enable me to take a step back, but Mark has far more experience of management than I do and can really push us on."
"We need to boost our squad with more quality and believe that Mark is the manager to bring better players to the club."
"He has won the division we are in before so we know we are getting a manager with good pedigree and a respected name in women's football."
The Ladies will be wanting to improve on this season's showing in the WPL Southern Division, where they eventually finished a somewhat disappointing 6th and missing out on a place in the new Women's Super Premier League.
There is good news already for the Irons, however, as former England goalkeeper Toni-Anne Wayne and forwards Becky Merritt (who recently won the Blowing Bubbles Ladies Goal of the Season Award for her strike against Brighton and Hove Albion Ladies) and Hannah Gowland committing themselves to the club for next season, as well as a large amount of interest from potential new players.
By David Blackmore