All in the family: Gary Green understands the owner's view.

Though he might one day inherit a real estate empire, Gary Green prides himself on being a self-made man. The son of SL Green Realty founder, Stephen Green, and the nephew of one-time Mayoral hopeful, Mark Green, Gary bears a striking resemblance to both in his appearance and perseverance.

After all, how many real estate progenies leave their father's firm to start a cleaning business?

That, however, came to be Green's dream after he did a brief stint at SL Green's management department.

"While at SL Green, I found that cleaning companies were not servicing the tenants too well and overcharging the owners, and I saw a need for a company that did it better," Green explains.

"So in 1992, I started Alliance Building Services and our approach to cleaning was 'How can we do a better job and save the owner money at the same time?"

Judging from Alliance's growth--the company now employs 15,000 people under all its divisions--the formula works, but Green prefers not go into the particulars of how he manages to provide better service at lower rates.

"It's kind of like asking Pepsi for their recipe," he Laughs.

"We don't want the people at Coke to find out how we do it."

He does admit, however, that he expects a lot from his staff.

"I come from a family of real estate owners, so I know how owners think," he says.

"For example, we ask the owner to tell us which ten ants' leases are expiring, so we make a concentrated effort to impress them. We know that when an owner is trying to retain a tenant, it's important to work along."

Green also makes sure that every last doorman receives appropriate supervision.

"The cleaning industry has this stigma about it, people say 'All those companies hire from the same labor pool, so how much of a difference can there be?'" he explains.

"Well, the key to being different is training, education programs and supervision. The way I gauge whether we're supervising enough is when I go into the field and see whether our staff has enough uniforms, whether the uniforms are clean enough, whether everyone knows what their exact role is. The important thing is not to skim on your supervision."

In the two years since the WTC terrorist attacks, Alliance has also been concentrating on security and messenger services. According to Green, while most owners used to see security as just an extra expense, they are now concerned with getting qualified personnel to handle possible threats.

"Our messenger center company is really a compliment to our security component," he says.

"Any time you can limit the access to the building, you improve security. The messenger center provides people who take packages from messengers and deliver them to the tenants, so no outsiders enter the building. We feel that if we are already in the building to provide security, we should go that extra step."

Alliance employees also work closely with the New York Police Department in order to update their clients on what they need to do in a worst case scenario.

"We incorporate a lot of NYPD programs into our security management, including Apple Alert and Application Laptop," Green says.

"We teach them about counter-terrorism measures. If we can give our clients the knowledge they need, in addition to giving them a good guard, we really are different."

So far, Green is happy with how Alliance is progressing. In his estimate, the firm, which functions as an umbrella for a number of cleaning and security-related companies, is growing at the rate of about 25% annually.

He has just signed a big contract with Trinity Real Estate--something he has been working on for the past 10 years.

"They feel we've become more established in the industry, so they can trust us," he explains.

"They are now more comfortable with our size."

Still, he admits that his boundless energy doesn't let him rest for long.

"We are always looking to buy new companies," he says.

"We just bought another messenger center service because we want to make these things a necessity in the business."

In addition, he keeps himself busy with his young son, his charity work and his impressive Mets collection: "I love the Mets because I love the underdog," he explains.

"Everyone usually roots for the Yankees because they win, but I love to see the weaker guy get his day."

As to the possibility of his one day entering the political arena, like his famous uncle, Green says it's not completely out of the question. "It's a possibility," he grins. "But I don't think my wife will be thrilled to find this out."