Transact SQL :: Pivot On Multiple Results

I have a table similar to below:

itemID | part
1         | A
1         | B
2         | A
2         | A
2         | A
3         | C

I need the table to look like the following:

itemID | part1 | part2 | part 3
1         | A        | B       | null
2         | A        | A       | A
3         | C        | null    | null

There will _never_ be more than three parts to an item, and it does not matter what order they are in.

I cannot get pivot to work for me.