I Love You, Man

Paul Rudd

Peter Klaven

Jason Segel

Sydney Fife

Rashida Jones

Zooey Rice

Andy Samberg

Robbie Klaven

J.K. Simmons

Oswald Klaven

Jane Curtin

Joyce Klaven

Jon Favreau

Barry

Jaime Pressly

Denise

Rob Huebel

Tevin Downey

Thomas Lennon

Doug

Sarah Burns

Hailey

Lou Ferrigno

Lou Ferrigno

Greg Levine

Hailey's Date

Jean Villepique

Leanne

Kym Whitley

Female Co-Worker

Colleen Crabtree

Female Co-Worker

Caroline Farah

Female Co-Worker

Mather Zickel

Gil

Aziz Ansari

Eugene

Nick Kroll

Larry

Liz Cackowski

Zooey's Friend

Kulap Vilaysack

Zooey's Friend

Catherine Reitman

Zooey's Friend

Carla Gallo

Zooey's Friend

Vicki Davis

Zooey's Friend

Josh Cooke

Alan (Bench Press Guy)

Jay Chandrasekhar

Barry's Buddy

Seth Morris

Barry's Buddy

James P. Engel

Barry's Buddy

Jerry Minor

Berry's Buddy

Joe Lo Truglio

Lonnie (Voice Crack Guy)

Murray Gershenz

Mel Stein

Keri Safran

JAR Waitress

Greg Tuculescu

Open House Couple

Ian Roberts

Venice Broadwalk Jogger

Bob Cicherillo

Venice Boardwalk Bodybuilder

Ethan S. Smith

Sidney's Buddy

Nelson Franklin

Sidney's Buddy

Ping Wu

Mr. Chu

Jill Bartlett

Woman Leaving Sydney's House

Matt Walsh

Impatient Golfer

Geddy Lee

Geddy Lee - Rush

Alex Lifeson

Alex Lifeson - Rush

Neil Peart

Neil Peart - Rush

Melissa Rauch

Woman Jogger Yelling at Sydney

David Wain

Wedding Photographer

Raquel Bell

Saks Fifth Avenue Saleswoman

Larry Wilmore

Justice Of The Peace

Dennis James Anderson

Hank Mardukas

Craig Wedren

Wedding Band

Damian Kulash

Wedding Band

Timothy Nordwind

Wedding Band

Dan Konopka

Wedding Band

Andy Ross

Wedding Band

David Krumholtz

Sydney's Buddy (uncredited)

Sidow Sobrino

Rush Concert Fan (uncredited)