This is a response I wrote to someone who asked me about ESTjs via PM. I decided to post it.
I'm afraid that my description of ESTjs will be a bit biased by my own experiences with specific, unhealthy ESTjs as well as my intertype relation with them, but I'll give it a shot.
ESTjs are the work hard, play hard types. They bust their asses during the week at work, often working overtime, but then at night after work they will just relax for a few hours. These periods of rest are just that though... ESTjs become restless and depressed by long periods of inactivity. The ones I know enjoy working out. The weekends are for partying (if they're not working overtime lol). The ones I know like to ask questions of people and get specific information about them, but offer very vague information about themselves and get irritated if you try to get them to be more specific and cough up facts. They see their business as their business, but also see your business as their business... this could be a battle of the Te's with me though, an intertype power struggle. The ESTjs I knew also seemed to believe that they're good at manipulating others to get what they want, but it was always painfully obvious when they were trying to be sneaky. ESTjs are the most "normal" type, and generally follow society's norms. They walk like soldiers... upright with shoulders square and head held high, but their gait has a bit of a cocky swagger. One of the ESTjs I know is emersed in his job at a club run by Sicilians, and he is also emersed into drug culture. As a result, his ideas of "normal" are skewed, but he still adheres to them. His walk is also a bit different. He tries to be more fluid. He looks a little silly sometimes... like he thinks he's a rapper or something. In spite of his "gangster" mentality, he is similar to most ESTjs in that he appreciates family values. He definitely intends on having a family of his own once he's done partying (he's only 22). The "wanna be gangster" ESTj believes that teaching children about life and looking out for children's best interests is everyone's responsibility, not just the child's guardians. I think many ESTjs kinda see family as the whole point of life. This could be partially due to their dual seeking function are partly due to their desire to fulfill society's expectations of them. They also seem to have an affinity for the military, at least from what I've seen. ESTjs value loyalty and try to be kind and loyal people. They can also be very generous, though sometimes it looks like they're trying to buy friends. One of the ESTjs I know would on occasion bring groceries over to my brother and sister in law's house and use their kitchen to make a meal, leaving the leftovers with them... he knew they could barely afford groceries, much less regular, traditional meals. Another thing I have noticed with ESxjs is that they are very concerned with their mate being attractive. The ones I know are unwilling to even consider unattractive, or even average or plain people for relationships.
ESTjs are also fussy about the organization of their surroundings, something that caused a lot of problems between me and the 2 ESTjs that I lived with. I would even go as far as to say that it was the main reason my ESTj husband and I divorced. Another reason we fought was the management of our finances. He'd get irritated when I talked about how important it was for us to invest. On one hand, I saw investing as an absolutely essential and necessary thing to do. On the other hand, however, neither he nor I was good at exercising moderation in spending. The result was an overextended household budget. I'd sit there going over our bills and I'd begin to feel frustrated because there was nothing left to invest. When I'd complain, stating how critical investing is, he'd become very frustrated and defensive and we'd start arguing. At the same time, he'd be frustrated by the lack of organization in our home and the dishes in the sink, and strike back at me by criticizing my domestic skills (or lack there of), something which I am EXTREMELY sensitive about. It was a downward spiral, and as time went by, the issues went beyond those basic types of arguments. As I became more distant, he became more aggressive. He'd say, "how come you'd rather be at work than at home?" (lol yes, an ESTj said I was working too much... 2 full time jobs isn't conducive to marital health) and I'd say "because I don't get yelled and bitched at at work!" I knew the relationship was over when he said that I was a bad mother and I realized that there was absolutely nothing he could say that could hurt me anymore. A few weeks later, I knew the marriage was over when a friend of mine said "Joy, my parents divorced when I was a kid. The only thing worse than having parents who aren't together is having parents who shouldn't be together." I didn't want my son to grow up thinking that that's how relationships work. I knew that his father and I brought out the worst in eachother, and I didn't want Travis see his dad's temper and aggression come out everyday like it was.
The other ESTj that I know quite well was part of my group of friends and dated my sister for a while. He and I were arch rivals for a while. It seemed to be a bit of a power struggle. I learned that he and I could get along very well if there wasn't anyone else around. We even had a very good understanding of eachother. Once he and I hung out by ourselves for a while, it was much easier to get along in group situations. He moved in with me and the INTj I was with for little while when my sister was dating him. It turned ugly very quickly. He rearranged my kitchen for crying out loud! The power struggles ensued once again. After he moved out we were able to get along quite well. For the last year of my relationship with the INTj I was with, this ESTj tried to plant little doubts about the relationship in my mind. It was apparent that he was trying to be "sneaky" in the way he was trying to convince me to split up with the INTj. He also frequently complained that all of the attractive women were "married or engaged or something". After the INTj and I split up, he came over one day and met Peter... he was going to get something for us, and Peter gave him $60. He left with it and I haven't seen him since. He's not the type that would generally do something like that, meaning he must have taken it pretty personally.
Anyways... I'm afraid there isn't much more I can offer about ESTjs. I can see how an INFj could bring out the best in them. Perhaps someone else will have a better description of ESTjs. As I've already stated, the ESTjs I knew weren't the healthiest of people.