Hiring senior people into a company can help accelerate your growth. But done poorly it can also change your startup culture in ways that can set you back many months. And remember, no matter what your board or investors have told you about how much they like certain candidates or what to look for, at the end of the day, it is the CEO’s responsibility to build the right team. So no matter what pedigree a candidate has, no matter how highly recommended, it is always your responsibility. If you are not comfortable with a candidate, don’t hire them.

First, a word of caution when hiring senior leaders. Everyone who has put in a decade or more into their profession and risen through the ranks is going to look pretty good on paper and sound great in an interview. Your job when you interview them isn’t to trip them up, but you will need to probe to understand in some detail what they have done and what others did in the organization. Sure Sally Sales may have grown the revenues of an admired company from $10m annually to $200m over several years, but was she the driver or a passenger? What were the specific initiatives she ran that led to the growth? What were patterns she uncovered that identified more profitable customer segments? How did she evolve pricing and packaging to improve upsells? What campaigns did she develop with Marketing? How did she train her team to compete against larger, more established competitors?

Your job is to try to understand what the candidate can do for you. I have found the best way to do this is to drill into examples of the work they did and then share the hard problems you’re dealing with in your own company. You want to understand their thought process. It doesn’t mean that everything they say will be directly applicable to your business, but you want to understand how they think and what they can bring to the table.

If a candidate declines to weigh in on questions about your business because of a lack of information, gently ask them again. If they still demur, do not hire them. In a startup, you never have perfect information and executives who always want more data, more information, more time are unlikely to change their behavior once they are inside the company.

If you don’t get two or three good ideas when interviewing a senior executive, don’t expect to get any once they’ve started. Also, be careful of any execs who “have a playbook” because sometimes it means they have one style and one way to operate and if your company is a bit different, well, they’re going to keep using their same tried-and-true approach no matter what happens.

I think it’s good to share real problems that you are facing to see how candidates would approach these problems. After all, if you hire them, these and other problems will be what they need to work on. And since not every candidate will make it to the finish line, you might come away with a more diverse perspective on things.

I am always skeptical of big company executives who claim they want to work in a startup. Anyone who has spent six years or more inside a 3,000 person or larger company in unlikely to be able to operate in a startup without a massive budget, a big organization a slew of consultants, unless they joined the company when it was still small or through an acquisition. In general, large company executives operate as caretakers in existing steady-growth businesses. Which is fine if your goal is to rinse-and-repeat existing operations. But if you’re trying to innovate, get to product-market fit and launch new things, you need people who are flexible in their thinking and can get stuff done themselves.

It is unlikely that big company execs will be willing or able to roll up their sleeves in an environment that demands hands-on action, rapid decision making and focused execution. Worse still, they can bring big company process and politics that kill the momentum you need in a startup.

Finally, always check references personally. Do not delegate this to the recruiters. Ask about their impact, what projects they led, how they got along with others. And always ask the fundamental question: would you hire them again? If you get anything less than a glowing endorsement, keep looking.

Have you seen big company execs be effective in a startup? Let me know your thoughts by posting a comment below.