Much more than a to-do list for the inept, a checklist can be an incredibly effective tool for professionals and experts. Using a well-crafted checklist in complex situations ensures we catch potentially fatal errors and dangerous oversights.

Many of us work in complex or high-pressure environments that, like the field of medicine, demand care and precision, such as in finance or the restaurant industry. The good news is that, in such intense environments, checklists really make a difference in helping us work more effectively.

We can be stubborn when it comes to making checklists for ourselves, especially when we know exactly what we are doing. However, it is often the skilled professions that benefit the most from making a checklist. One of the reasons for this is that we often skip over or forget the obvious “dumb stuff,” falsely assuming that focusing on more complex things is far more important. The dumb stuff, however, is often essential to the procedure at hand. Using a checklist helps you avoid letting the necessary stuff slip through the cracks, and you just might find you make far fewer errors because of it.

Take, for instance, chef Jody Adams at Rialto Restaurant in Boston. The checklists Jody uses are what most would call recipes. Yet recipes and checklists share the same function: they tell us what needs to be done and when. In addition to having her recipes on display at her kitchen workstations, the restaurant staff also make checklists to ensure the special requirements of individual customers are met. Once the dishes are ready to be served, they receive a final check by the sous chef or Jody herself to make sure they meet Jody’s standards. This checklist system enables Rialto to deliver consistently exquisite dishes to customers, and it is no surprise that Jody has won awards for her expertise or that the restaurant often makes “best-restaurant” lists.

Financiers, too, can use checklists to help them avoid unnecessary risk as a result of rash or uninformed decisions. “Cook,” an anonymous investor and director of a fund worth billions of dollars, uses a “Day Three Checklist,” which helps him and his team decide whether to invest in a company or not. The checklist offers Cook a huge advantage: efficiency. This careful and quick method for evaluating investments gives him an edge over other investors.

From ensuring high-quality dining experiences to helping rake in the big bucks, the unassuming checklist is a versatile tool that can yield impressive results and be applied to a variety of different situations. It’s hard to imagine that a simple checklist could make a significant impact on the world. Yet medical programs studying the use of checklists have shown that they have prevented mistakes, saved money and – most importantly – saved lives.

One study carried out by critical care specialist Peter Pronovost, called the Keystone Initiative, aimed to reduce the number of infections from central line catheters inserted into the veins of intensive care patients. Central lines are easily and frequently infected (for example, by being touched with unsterilized hands), causing potentially lethal complications for patients. Pronovost employed a checklist to see if it would reduce infections. It was a success; the initiative ended up saving $175 million and 1,500 lives over 18 months.

Drawing inspiration from Pronovost and the fields of engineering and aviation, the author and the World Health Organization developed a checklist to be tested in eight hospitals around the world, in what was named the Safe Surgery Saves Lives program. The hospitals were asked to use this surgical checklist, which consisted of nineteen essential items ranging from discussing the patient’s expected blood loss to confirming that they actually had the correct patient. The results were astounding; deaths from surgeries across the eight hospitals were reduced by 47 percent.

Checklists are as simple as they sound: a list of steps to be completed when carrying out a procedure. Surprisingly, it is the obvious steps – stuff that everyone should know – that are often most crucial and yet forgotten or skipped. The checklist functions as a safety net to make sure we catch the obvious stuff, such as asking, “What kind of weapon was used?” before we proceed any further. Once the basic stuff is checked off, we are mentally better equipped to tackle the more complex or unpredictable issues that are unique to each patient.

Checklists should be as short as possible, include all essential steps and leave no room for misunderstandings.

It’s easy to scoff at checklists, particularly as many of us think of them as scrawled reminders or glorified to-do lists. However, when they contain all essential items, and are concise and usable, checklists become powerful tools.

One essential aspect of a checklist is that it contains the “killer items” of the procedure. These are the steps that are easily disregarded but, if not completed, could be disastrous. For example, this could be a reminder to identify a patient’s allergies before surgery.

Although they should contain all essential items, checklists should not be thorough guides. Daniel Boorman, a veteran pilot who creates aviation checklists for Boeing, says that around five to nine items are ideal, and there should be a time limit on how long it takes to go through the list. After around one minute of reading a list, people can become distracted and skip vital steps.

A checklist should also be user friendly. For example, a surgeon while implementing an early version of his checklist, confused a nurse in his team right before a surgical procedure because it was unclear how the checklist should be used. The nurse had checked off the steps for the procedure before it had even started, rather than – as the surgeon had intended – reading out each step to the surgical team and checking them off as they went.

To avoid confusion, it should be clear whether the list is a “READ–DO” (read out the step, then complete it) or a “DO–CONFIRM” (complete the step, then confirm you have completed it). Lists should also be written in the language users are familiar with; for example, “fire mushrooms” (meaning “cook the mushrooms now”) in a restaurant.

The next time you create a checklist, take care to ensure it is precise, user friendly and includes only items of the highest importance