This is from an Amazon review of Marcus Buckingham’s DVD resource, The Truth About You. It describes what a strength actually is very well:
Buckingham’s advice to success is simple: Work on your strengths. But it is his definition of “strength” that makes a world of difference.
To him, strength is not something you’re good at but something that excites you, something that you look forward to, something that makes you strong. The idea of focusing on how it feels when we’re doing something rather than on how well we perform it has changed the way I look at my life and my work for the better. Now I don’t feel embarrassed that I’m not good at math or regretful that I did not follow my teacher’s advice (you’re good at writing; therefore, you should be a lawyer). Instead, I give myself permission to concentrate on using what I’m good at in ways that make me feel accomplished and fulfilled. That does not necessarily mean it will translate into buckets and buckets of money. However, it sure beats waking up every morning to go to a job you do well but dread and hate.
Related to this is my post from a few months ago, “Your Weaknesses Are Not What You Are Bad At.”
For those seeking to get a better picture of their vocational direction (and I mean first of all in your current job, rather than finding a different job), I would recommend Buckingham’s DVD set.
The most helpful thing about it is actually this little book that comes with it in which you record, over the course of a week, the things that weakened you and the things that strengthened you. By reviewing going through this exercise and then reviewing your entries you can get a better idea of your strengths and weaknesses (and remember: your weaknesses are not necessarily what you are bad at; they are what drain you).
If you are interested in a more in-depth treatment of strengths and how to get a better picture of what your own strengths are, I would also recommend Buckingham’s book Go Put Your Strengths to Work.