Query Help: Grouping Like Rows

I have a table that has 2 colums.


Room_Number Items
1 Chair
2 Chair
2 Desk
3 Table
4 Computer
4 Radio
4 Book
4 Chair
6 Fish Tank
6 Chair


I want a query that will select rooms 1-6 and include all items for those rooms on one row. Example below


Room_Number Items
1 Chair
2 Chair, Desk
3 Table
4 Computer, Radio, Book, Chair
6 Fish Tank, Chair


I hope this makes sense. Thank you in advance.