While the term "emotional intelligence" was first defined in 1990 by psychologists John D. Mayer and Peter Salovey (the latter went on to become president of Yale), it took the 1995 release of Daniel Goleman's Emotional Intelligence to popularize the concept.

Like most lasting ideas, the importance of emotional intelligence seems obvious in hindsight. Research shows developing greater emotional intelligence can lead to higher performance and pay as well as better professional and personal relationships.

As Inc. colleague Justin Bariso defines it, emotional intelligence is the ability to make emotions work for and not against you.

The obvious part? The better you can understand and manage your emotions -- and the emotions of people around you -- the greater your chances of success.

Which means most of us feel like we're emotionally intelligent. After all, I (mostly) manage my emotions. And I'm sometimes able to both motivate and inspire other people, as well as talk them down from an emotional ledge.

But that doesn't mean I have high emotional intelligence -- which is why Goleman recently distilled emotional intelligence into four domains and 12 core competencies.

Here they are:

Domain 1: Self-Awareness

1. Emotional self-awareness

Domain 2: Self-Management

2. Emotional self-control

3. Adaptability

4. Achievement orientation

5. Positive outlook

Domain 3: Social Awareness

6. Empathy

7. Organizational awareness

Domain 4: Relationship Management

8. Influence

9. Coach and mentor

10. Conflict management

11. Teamwork

12. Inspirational leadership

Self-awareness is fairly self-evident: knowing what you feel, why you feel that way, and how those feelings either help or hinder you. And knowing your strengths and weaknesses and when to ask for help.

Self-management is also obvious. Managing how you respond, especially in times of stress, conflict, or adversity. Staying focused on your goals. As Jeff Bezos puts it, a sign of high intelligence is the willingness to change your mind when you uncover new information or new perspectives.

In simple terms, social awareness is empathy: listening to others, paying attention to others, and finding common ground. The ability to put yourself in other people's shoes -- or, more broadly, to put yourself in your organization's "shoes."

Relationship management involves a number of skills. Motivating others. Mentoring others. Dealing effectively with conflict. Applying an occasional dose of tough love (in pursuit of a positive, not negative outcome).

Referring to the four domains, Justin writes:

Each of the four abilities is interconnected and naturally complements the others; however, one isn't always dependent on another. You will naturally excel at certain aspects of the four abilities and display weaknesses in others. For example, you may be great at perceiving your own emotions, yet you struggle to manage those feelings.

The key to strengthening your emotional intelligence is first to identify your personal traits and tendencies and then to develop strategies to maximize your strengths and minimize your weaknesses. 

To do that, take a second and skim the domains and competencies again.

Some will immediately jump out as weaknesses. (For me, conflict management, organizational awareness, and coaching and mentoring are definite areas for improvement, in part because for the past 10 years or so I've experienced far fewer situations where those skills are necessary.)

Then pick one area of weakness and get to work. (Here are 10 ways to increase your emotional intelligence.)

Since the domains are complementary, improving that competency will naturally increase your emotional intelligence in other domains and competencies.

And increase your chances of success.