Let’s do a quick check. How would you answer this question? If I could increase your sales tomorrow by 20 percent, could you handle the increase while:

• being 100 percent on time, to your very first commitment;
• without going into firefighting mode and
• still maintain a competitive lead-time?

 
If the only way that you could handle the increase is to increase your lead times, work overtime, or miss due dates, then you have an internal operational constraint. You don’t have a market constraint.

On the other hand, if you can answer yes and you could take a 20 percent increase in sales and not have any negative effects, then you do have a market or sales process constraint.

Lang, L. (2010). Mafia Offers: dealing with a market constraint. Theory of Constraints Handbook. New York: McGraw-Hill, 603-628.