As a member, you can invite colleagues who you feel would find the site useful. Look for the ‘Invite contacts’ item underneath your ‘My page’ menu tab – it will be visible if you mouse over the ‘My page’ tab on the main menu. That will take you to a page where you can send invitations to individuals (click on the ‘send invitations manually’ icon) by giving a list of email address, use an existing address book, or just copy and email the invitation link on the page.