The following are some questions to consider as you weigh whether a PhD is right for you: 

• What are your interests? How do those interests map onto a potential career and the need for additional education?
• Are you interested in research and the discovery of new knowledge? If so, a PhD could be a good fit.  Alternatively, do you prefer the implementation of ideas to solve problems? If this is your preference, then a PhD may not be necessary.  More generally, ask yourself whether a PhD degree is a necessity, a bonus, or not at all necessary to do the work you want and have the career you prefer.
• Would you benefit from more time (out of school) thinking about the above questions?

It’s OK to apply to graduate school even if you graduated (as an undergrad) several years ago. It is not uncommon for students to work in the public/private sector for a few years before returning to school to pursue a graduate degree. Oftentimes the out-of-school experience can provide valuable experience and reflection about what you choose to study in graduate school.

If after answering these questions if you are fairly certain you want to get a PhD, then you should peruse the other sections!