Last week the RM by Roland Mouret Rainbow Collection was launched on Net-A-Porter.com.

In order to celebrate this colourful collection Roland invited some of Hollywood most beautiful women to wear the looks at his launch party in LA last night.

Heidi Klum picked a stunning lavender RM By Roland Mouret violet silk mini dress which showed off her post-baby figure perfectly.

It’s such a shame about the white Trib Two’s.

Devon Aoki was equally colourful wearing a bright yellow RM By Roland Mouret silk mini dress, which she later paired with a leather jacket and studded clutch.

I love how this gives her a teeny tiny waist.

Olivia Wilde was more muted wearing a RM By Roland Mouret blue stretch silk dress.

Her look was also paired with a leather jacket and a Christian Louboutin Viola nappa clutch, which has a cute sculpted leather floral detail.

Over her black draped maxi dress, Rachel Zoe opted for a RM By Roland Mouret Zephyr silk brocade jacket which just shot to #1 on my wish list.

Demi Moore didn’t get the rainbow memo so she opted for one of Roland’s classic LBDs.

You can barely make out the folds on her beautiful one-shoulder dress.

I’m more in love with Amber Valletta’s RM by Roland Mouret Autan textured wool coat and Chanel clutch, than her Spring 2010 black and grey RM dress.

I wish she had worn one of the more colourful pieces.

Credit: Style.com, Getty & Zimbio