Certifications are the validity of the knowledge and understanding you say you have. It is a way for employers to understand what you are bringing to the company without going through an extensive Q&A with the prospective employee. According to statistics made on major big organizations managers say that they screen resumes based on certifications and certified employees earn 35% more than non-certified employees. This is regardless of a degree. If you are going to be successful in your industry and get the kind of money you deserve, you are going to have to obtain a certification.