ASGN Inc — Director's Dealing 2010

May 4, 2010

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: ON ASSIGNMENT INC (ASGN)
CIK: 0000890564
Period of Report: 2010-04-30

Reporting Person: McGowan Michael (CEO - Oxford Global Resources)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2010-04-30	Common Stock	D	1190	$7.03	Disposed	263504	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	5000	Indirect

Footnotes

F1: Executive officer elected to satisfy tax withholding obligations upon vesting by having On Assignment, Inc. withhold a number of vested shares equal to that of the employee's tax liability.