The Lords Alliance was formed mainly to stop the growing influence of the Black Network. The Zhentarim has been trying to corner the mercenary/protection business for centuries and they've come close a few too many times. Since the alliance has formed the Zhentarim have majorly scaled back their efforts in the Sword Coast.
The alliance doesn't believe in a set code of conduct. Anybody that is against the Zhentarim and wants to see the Sword Coast prosper is welcome in the organization.
Laurel Silverhand: Open Lord of Waterdeep and current alliance leader and founder
Dagult Neverember: Lord Protector of Neverwinter and current alliance member
Ulder Ravenguard: Grand Duke of Baldur's Gate and current alliance member
Taern Hornblade: High Mage of Silverymoon and current alliance member
Northwest Faerun: Waterdeep, Neverwinter, Silverymoon
West Faerun: Baldur's Gate, Iriaebor