ENTPs in short:

Quick, ingenious, good at many things.  Stimulating company, alert
and outspoken.  May argue for fun on either side of a question.
Resourceful in solving new and challenging problems, but may
neglect routine assignments.  Apt to turn to one new interest after
another.  Skillful in finding logical reasons for what they want.

About 5% of the population.

Details about ENTPs:

ENTPs wish to exercise their ingenuity in the world of people and
things.  Found in about five out of every hundred people, ENTPs
extrovert intuition; thus they deal imaginatively with social
relationships as well as physical and mechanical relations.  They
are very alert to what is apt to occur next, and always sensitive
to possibilities.

ENTPs are good at analysis, especially functional analysis, and
have both a tolerance for and enjoyment of the complex.  Usually
enthusiastic, ENTPs are apt to express interest in everything, and
thus are a source of inspiration to others, who find themselves
caught up by the ENTP's enthusiasm.  This type is delighted over
many things and so is easy to please, often showing the
effervescence of their NF counterpart, the ENFP.

The ENTP is the most reluctant of all the types to do things in a
particular manner just because that is the way things have always
been done.  They characteristically have an eye for a better way,
always on the lookout for new projects, new activities, new
procedures.

ENTPs are confident in the value of their pursuits and display a
charming capacity to ignore the standard, the traditional, and the
authoritative.  As a result of this open attitude, they often bring
a fresh, new approach to their work and their lives.  The ENTP is a
keen judge of the pragmatics of both the social and the mechanical,
and may become expert at directing relationships between means and
ends.

Where the introverted NTP sees design as an end in itself, the
extroverted NTP sees design as a 'means'; the end is the invention
that works, the prototype that is replicatable.  Ideas are valuable
when and only when they make possible actions and objects.  "It
can't be done" is a challenge to an ENFP and elicits a reaction of
"I can do it."

They are not, however, the movers of mountains as are the INTJs.
Rather, the faith of the ENTPs is in their ability to improvise
something, and they display an unusual talent for rising to the
expectancy of a situation.

Superficially, ENTPs resemble ESTPs in their derring-do.  But the
focus of the ENTP is on competency and the sense of power this
gives, rather than on the feeling of freedom of action experienced
by the ESTP.

ENTPs can be fascinating conversationalists, able as they are to
follow the complex verbalizations of others.  They may deliberately
employ debate tactics to the disadvantage of their opponents, even
when the "opponents" are close associates and valued friends.

ENTPs are the most able of all types to maintain a one-up position
with others.  They value adaptability and innovation and thus
respond quickly and adeptly to another's shifting position.  They
may even be several jumps ahead.

The ENTP, talkative and motivating, is often the life of an
enterprise.  The ENTP can be an entrepreneur and cleverly makes do
with whatever or whoever is at hand, counting on ingenuity to solve
problems as they arise, rather than carefully generating a detailed
blueprint in advance.  A rough draft is all an ENTP needs to feel
confident and ready to proceed into action, counting on the ability
to improvise as a situation develops.

Because of this tendency to depend on ingenuity and improvisation,
they may neglect very necessary preparation at times.  After
repeated failures in situations where improvising has met with
defeat, the ENTP may develop ways of avoiding such situations as a
substitute to thorough preparation.

ENTPs can succeed in a variety of occupations, as long as the job
does not involve too much humdrum routine.  At this point, they
become restless.  If a project in which they are engaged is no
longer challenging, they tend to lose interest in that project and
fail to follow through - often to the discomfort of colleagues.

Seldom are ENTPs conformists.  ENTPs enjoy outwitting the system
and use rules and regulations within the system to win the game -
whatever it may be.  They understand well the politics of
institutions and deal with these realities very well, always aiming
to understand the people within the system rather than to judge
them.

ENTPs are good at innovative projects and can administer them well
if dull routine is not involved.  They usually are outstanding
teachers, continuously devising new participative ways to make
learning exciting for the students.

As an employee, an ENTP may work against the system just for the
joy of being one-up.  For ENTPs, to be taken-in, to be manipulated
by another, is humiliating; this offends their joy in being masters
of the art of one-upmanship.

ENTPs are the natural engineers of human relationships and human
systems.  Their good humor and optimistic outlook tend to be
contagious, and people seek out their company.

As mates, ENTPs tend to create a lively living environment.  They
are gregarious, laugh easily and often, and are typically in good
humor.

Orderliness in the routines of daily living is not apt to inspire
them; they usually solve this problem by mobilizing those around
them.  Tom Sawyer illustrated this talent when he solved the
problem of getting his Aunt Polly's fence whitewashed.  Life with
ENTPs is likely to be a daring adventure; they can lead families
into physical and economic dangers.  ENTPs improvise to remain
unaware that they do not have the necessary knowledge of the
situation to ward off such dangers.

If the mate of an ENTP is not competitive, he or she is likely to
find the one-up/one-down transactions somewhat wearing.  If the
mate is competitive, the result might be conflict.

Although usually good providers of economic necessities, ENTPs at
times engage in brinkmanship with their careers, placing them in
jeopardy and behaving as if unaware of the consequences; they may
thus offer unnecessary challenges to those who have power over
their professional success.  When challenges elicit negative
responses from superiors, ENTPs are apt to react with delight at
having an opportunity to improvise a solution to the crisis - and,
more often than not, they succeed in doing so.

ENTPs are likely to have all sorts of hobbies and to be experts in
unexpected areas, but they are not apt to share these hobbies with
their mates or children in the sense of teaching them.  In fact,
ENTPs may be very inconsistent in the attention given to offspring.

Usually, it is feast or famine.  ENTPs have a lively circle of
friends and are interested in their ideas and activities.  They are
usually easygoing, seldom critical or nagging.  At their worst,
they can show undependable, fickle characteristics and may be
easily discouraged.