Chief executive Marc Bolland said the Autumn/Winter 2013 ranges revealed at a catwalk show in central London represented "a step in the right direction".
"We want to be very clear that this is a step-by-step approach," he said, adding: "The team will keep on improving. What is important is the direction - and I am very confident that the direction is in style and in quality."
Mr Bolland carried out a major reshuffle last year amid sliding sales but insisted that the impact of the changes in clothing would not be felt until after this year's spring and summer lines, which were put together by the previous regime.
However, the executive makeover received a major setback when "Knicker Queen" Janie Schaffer walked out after just three months as director of lingerie and beauty.
Mr Bolland said he was confident in his new team, praising them for their "very, very hard" work.
"We have inherited a very strong brand," said Mr Bolland, who took over as M&S boss three years ago. "There is very strong quality, strong retail and branding."
"It is quality, and the best price, both at the same time," he said.
General merchandise executive director John Dixon - formerly M&S's head of food - admitted much of the British high street had "changed at a faster pace than we have" and that the chain was focused on listening to shoppers' needs.