The phrase "launch a collection" is correct and usable in written English.
You can use it when you are referring to putting something (like a book, clothing, artwork, etc.) together in one group or when introducing something new for sale or public viewing. For example: "We are proud to announce the launch of our new summer collection of dresses!".
Dolce & Gabbana is to launch a collection of hijabs and abayas targeting wealthy Muslim women in the Middle East.
It would be much better for H&M to launch a collection of dresses, with a designer, rather than just one," she says.
The Scottish designer returns to the city to launch a collection of rugs, finesse his coming furniture line and visit 10 Downing Street.
And earlier this year, Harry Potter actor Emma Watson teamed up with Italian designer Alberta Ferretti to launch a collection made entirely from environmentally friendly materials.
Undaunted, two of Nelson Mandela's granddaughters chose the eve of his 95th birthday to launch a collection of 299 rand (£20) T-shirts emblazoned with "Legend", "Revolutionary" and "Long Walk to Freedom".
If you're using a PC with Internet Explorer, you can hold down the control key while you click to launch a collection, which will override the pop-up blocker.
Last year, H Stern launched a collection of jewellery called Grupo Corpo, inspired by "the aesthetics of the body in motion".
UK designer Tom Cridland is also appealing to a new consumer, recently launching a collection of t-shirts and sweatshirts designed to last 30 years.
Last year, under the aegis of a parent company, Amsale, he launched a collection with his own name for the first time.
Philip Green turned Topshop around by bringing in up-and-coming London fashion week designers to create diffusion lines, then launched a collection by Kate Moss.
When she launched a collection in September last year, she said we should not buy new clothes for six months, which must have left her sales people wringing their hands.
