Roberto Di Matteo and Holland, promoted from reserve team manager, will coach the first team alongside Villas-Boas.
"Sometimes you can play football until you're 35 and at 45 you're considered experienced despite having only had 10 years thinking about coaching and managing," said Holland, who began coaching when injury ended his playing career at 21.
"For the guys that don't have those outstanding careers, your learning starts much earlier. At 21 I had my full coaching badges and, at the time, only Graham Taylor had been younger.
"Having not experienced the playing side, you work harder to find other ways of having an edge. In Andre's case he was with Bobby Robson at Porto, so to have the opportunity to work with a coach of his pedigree is exciting."