The Irish couturier, who is renowned for his classic and elegant designs, has created a typically ladylike and wonderfully tailored collection for autumn/winter 2015.
Timeless navy, black, beige, burgundy and ivory are the key colours in the collection, while O'Brien introduces yellow ochre for the first time.
Standout pieces are the boyfriend style coat with oversized silhouette, military jacket with velvet collar, silk pleated dress, and chic structured culottes.
There are also basics such as crew knit sweaters, roll neck polo shirts and white shirts which are the perfect go-to pieces for the season ahead.
Peter O'Brien for Arnotts culottes €195 and top €155
Peter O'Brien for Arnotts party dress €375
Peter O'Brien for Arnotts double hem dress €265
The 44-strong collection is available in store at Arnotts and online now, with prices starting at €95 for knitwear and going up to €495 for statement coats.