Not a new concept, as it is mentioned in every planning book.  The key point here is that one must realize how important this is as a step toward assuring that you are building a great life, rather than haphazardly building a structure that will not stand up to life's circumstances. 

If I don't know where I am, how can I map a path toward where I want to be and what I want in life?  And with no map, we must depend on hope, fantasy, luck, serendipity, circumstances...

Read, to solidify the importance:  The Importance Of Knowing "Where I Am" - Without Knowing This, There Is Vagueness And Lack Of Clarity.

Who I Am - If we believe we are something other than who we actually are as a being in life, then we misspend time and attention and worry on what is not necessary to protect or even work on.  Life is strengthened by knowing what the solid base actually is.  (Read the linked pieces to solidify this effectively.)

My Values - This is something we have "taken on" and added as if it were "self".  Knowing these is necessary, for they are the measure of worth of all we do in life and the essence of a core of self that is strong and effective.  And some are held as "beliefs" that may need to be corrected, if they do what harms our highest values.

My Core Life Skills - These skills are those which work well to create whatever other skills we want to develop, plus they get us what we want in life.  They are the most important, for without them we lack high effectiveness in life.  (I also call these skills "the basic life skills".)

My Skills

My Life Rated - This, of course, is the ultimate indicator: what results am I producing in my life - with the overall indicator of the level of my true, deep, ongoing, underlying happiness.

The Importance Of Knowing "Where I Am" - Without Knowing This, There Is Vagueness And Lack Of Clarity - And it will decrease your progress and happiness as you journey through life.