The path to billions in sales starts with a single step. Many entrepreneurs spend a lot of time trying to land a behemoth as their first client, when what they should focus on is getting their foot in the door, and winning enterprise a few seats at a time.

The late 1990s and early 2000s were the peak of large enterprise-software solutions. Companies invested millions in software that would take two to three years to roll out and planned to be in service for a decade. In those days, there was no "bring your own device," and companies definitely frowned upon users installing their own software.

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Today in enterprise there are still managers of managers of managers who make the “big decisions,” and that’s where million-dollar deals happen, but sometimes the best path to those senior directors and group VP’s is through their employees. 

It is really hard to get face time with a decision-maker at a medium- to large-sized business, and if you do, you will have to talk about why you are better than your competition, which may lead them to talk to your competition. Instead, make your enterprise software go viral, from the bottom up, by aiming for word of mouth.

Don't sell to management. Sell single-seat licenses to individual managers and workers, one department at a time, until it becomes standard for the entire company.

There are plenty of success stories, such as enterprise-communication software 15Five, where a single seat license at MailChimp grew to be a five-user license, and then went viral. Farrah Kennedy, senior manager at MailChimp, recalls how she was the catalyst that made 15Five go viral within MailChimp.

“I started using the free trial right away with two other managers," she says. "One of them also immediately loved it. He added two other managers, and then they added their coworkers. It then spread to other departments, not even because I told them. We all just charged it to our company AmEx.”

According to 15Five, Ben Chestnut, the CEO of MailChimp, got wind of the software and recommended it to his other company, Mandrill, which signed up for a free trial, and within one week eight managers had already signed up for paid licences. The users dictated the adoption, and the pervasiveness of 15Five made it the standard.

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Once entrenched, other apps or software are unlikely to replace it. This is actually a pretty common occurrence. Users start using Gmail, and suddenly the organization moves off of Exchange and on to Gmail for Business. That move leads to users trying Google Docs, which leads users to not use Microsoft Office.

Word of mouth to the user is how enterprise software goes viral.

Owning the relationship with the user also lets an app provider learn from the person using the software, rather than an executive who likely doesn’t know the pain points of the user.

Aya Zook, of Microsoft Ventures, told me at Global Startup Day that “when it’s the enterprise space, entrepreneurs have to go deep on the listening side. That’s just as valuable as what the software can do for the enterprise.”

No matter who you are talking to in enterprise, Zook says it is important to remember that this is a long-term conversation,

“When dealing with corporate, you’re in it for the long run," he says. "It’s not about having a meeting, getting people excited so they can cut a check, this is like having a strategic conversations over a course of time.”

This can be a challenge even when selling to the user. When a worker in a company is evaluating if they are going to help automate part of their job, they need to know that the tool is going to be around for a while.

There are many paths to enterprise sales, but for the entrepreneur the quickest path to adoption is selling to the user, not managment. Sell from the bottom up to grow organically within enterprise companies, and remember, be tenacious because sales cycles can move at the speed of the corporations you’re selling to.

Related: This Startup Landed Groupon as Its First Customer. Here's How.