Work experience doesn’t necessarily mean you are a subject-matter expert. It could mean you know more than some people. A true subject-matter expert (SME) must have deep understanding of a particular process, function, or technology; must have studied the field; and must have spent hundreds—even thousands—of hours mastering a specific business topic. An easy way to define an SME is that this is a person who knows a great deal more about the topic than others with comparable experience. That being said, you may still be called an expert just by understanding more than others.