Since I am not a professional trader my opinion on this book is probably of limited value. Forewarned, my thoughts on this book:The intended audience for this book seems to be professional traders who, somehow, already know they have an advantage in the market and are looking to up their profitability even more. Professional does not necessarily mean it is their only job but all the examples in this book are from people who are full time traders. The author does not spend any time on discussing why, theoretically, it should be possible that anybody is able to beat the markets consistently or what traits those who can tend to have. Also, beyond the psychology of it all, there is no serious discussion of what elements a trading plan should include. The author assumes the reader already has these things in place. Nevertheless Tendler is quite familiar with trading concepts such that he can discuss specific factors affecting the psychology of it all while staying down to earth.Indeed, the book's greatest strength is the balance it strikes between theory, real life examples, concrete action plans and nitty-gritty details. The author never talks about problems traders tend to run into without also discussing very specific plans for how to deal with them. This typically involves what specifically to write down in your analysis or, less frequently, other concrete things to do, e.g. if such and such is a problem set up automatic reminders to do some kind of analysis or force yourself to take breaks throughout the day.One way in which this book is different from other books is to emphasize that traders, almost by definition, are fiercely competitive and can often be too hard on themselves as they hold unrealistic ideas about the attainability of perfection and ignore that there are factors beyond their control. For example, they might kick themselves for not reading an article that popped up during the day that could have helped them avoid a loss or score a gain on some trade. This, of course, is not realistic. Time is finite, so you cannot read everything. Given that, missing a key article is inevitable from time to time. Tendler's whole approach is to look at a trader's persistent problems and identify what irrational thoughts are causing them and then go on to make a very concrete plan on how to limit the problems.Tendler's approach seems like something which should work providing that the reader really does have an edge in the market. For those who have played poker much of what happens in trading and the problems that arise will seem almost completely identical. Although I have not read Tendler's books on poker, I have played the game and would be very surprised if the poker books were not nearly identical. In poker it is easier to develop a model on what the course of events would look like even if you had an edge. There would still be big losses, mistakes which seemed obvious in retrospect, and long losing strikes. In blackjack it would be even easier to model since the precise edge for card counters is known and still subject to the same "issues" affecting one's psychology while playing. Given a mathematical advantage it is all fairly straightforward to have a mental model of. On the flip side, without a mathematical advantage no amount of psychology is going to change reality and thinking that psychology could help will probably make matters worse. It is completely the reader's responsibility to determine whether they really have an edge or not.Overall, I found the book to be logical, have specific actions plans and I think that the emphasis that often the problem is that you are too hard on yourself as opposed to not being hard enough is a key theme not yet common.I am guessing that the author's decision to leave out topics of why it is reasonable to think anyone should have an edge in the market (i.e. the efficient market hypothesis is wrong) and what traits such people have is due to thinking it would not really add any value. Perhaps, he thought, due to confirmation basis everyone will see such traits in themselves whether they really have them or not. This may be somewhat true, but if the intended audience is professional traders who do have an edge, it seems logical that they are less prone to confirmation bias than others and, as such, could realistically evaluate how well they score on the requisite traits and know where they needed to work.Finally, Tendler emphasizes tracking one's emotions with the ultimate goal of setting up a "distant early warning system" (my phrase not his) of pending blowups. The ultimate goal is not only to detect pending disasters early, avoid them, but also to lessen these emotions once they are too strong. I agree with this plan but my own feeling is that emotions should be tracked for another reason that has to do with how similar trading is to poker. There is a small hint at a key similarity between poker and trading in this book, but no elaboration.I would like to rate the book 4.5 but the 5 point scale forces me to choose, so I round up: the parts that are missing do not take away from the core themes although I do think they would have been helpful to include.