The joint appearance comes as the committee embarks on a wide-ranging study into security threats facing Canada, which was launched a week before last week's attacks.
CBC.ca will have full coverage of today's meeting, which will get underway at 1 p.m. ET.
Later today, Public Safety Minister Steven Blaney is expected to table a bill that would strengthen CSIS's powers to monitor and track those suspected of plotting terrorist attacks.
On Sunday, Paulson put out a statement indicating the RCMP has evidence, including a video made by gunman Michael Zehaf-Bibeau, that suggest the attacks in Ottawa were driven by ideological and political motives.