When people ask me about which process in their business they should professionalize first, I inevitably tell them to start with sales. In case you haven’t picked up on it yet, I’m a big believer in sales, and it’s no coincidence that I tend to give it the highest priority. A refined and professional sales process is an asset that will deliver great returns for your over and over again throughout the life of the business.

Why start with sales? Because it’s hard to uproot and replace an entrenched sales system — even one that doesn’t work very well — and every day you wait, the more difficult it becomes. If there’s one thing you want to get right as early as possible, it’s sales.

To a large extent, your company’s growth will also be limited by the professionalization of your sales process. By putting a professional sales process in place, you’re doing much more than simply generating more revenue: You’re growing your customer base. By scaling your efforts and making them more efficient, you’re also driving down your costs for acquiring new customers. The more efficient that process becomes, the fewer resources it takes to find new customers and bring them in.

Once you have your sales process fully professionalized, what’s next? For my money, it’s customer service. This element of the business can be called a number of different things, from customer care to client services, but the core function of the process is the same. If sales is about going out and generating the customers, customer service is keeping the customers you already have.

Another way I’ve heard this put is that sales are the “promise makers,” and customer service are the “promise keepers.” If you want to keep those customers happy, you need a professionalized customer service process in place. It’s the only way to keep those hard-won clients and customers as content as possible, and ordering from you for a long time.

Wrapping up the revenue-generation side of the business, I’d focus on professionalizing your marketing and advertising. In some business models, particularly online ones, marketing may actually take on some of the functions of sales, and in those situations it will obviously be a higher priority.

What makes a marketing process professionalized? Trackable results. If you can accurately track what’s working and what’s not, it becomes possible to make highly informed decisions about where to spend your marketing budget to see the best return. When you’re throwing money at radio, TV, and online ads, the one thing you need to know is what’s working.

Some kinds of marketing are much easier to track than others — online marketing generally delivering the highest level of detail — but all forms of marketing are trackable to some degree. One of the simplest ways to put this in action is simply to ask your new customers “How did you hear about us?” The more professionalized your marketing, the more efficiently you gather than make use of that feedback (using tools like A/B testing, for instance).

Sales, customer service, and marketing are all in the “generating revenue” bucket I mentioned in part one of this series. All three support the central goal of attracting and retaining customers. But this is just one side of the professionalization process. Next, I’ll talk about the other side: Managing expenses.