Keira Knightly is the picture of cool in a midi monochrome party dress

Now we all know what it's like when you simply cannot decide what to wear for that special occasion. Should you go for something colourful or stay loyal to your trusty LBD? This season's fever for two-tone dresses lets you have your cake and eat it while staying tip-top on trend- perfect! Kate Winslet recently took advantage of the monochrome mania in a curve-hugging, panelled number but this week we've diverted our affection to the beautiful Keira Knightley who rocked the look to perfection in London this week. Keira's stunning ensemble has an undeniable retro edge with a sniff of swinging sixties, brought bang up to date with a figure flattering wrap top and mid-length hemline. Colour-blocking is one of A/W 2011's hottest topics and Ms. Knightley shows us how to do it in style. If you're loving the look and fancy a two-tone treasure, make like Keira and keep the colour blocks simple and minimalistic for stylish sophistication. Here are some things to add to your Christmas wish list to get you season-savvy in three swift steps...