Executive Toughness. This week’s blog is a book review:  Executive Toughness: The Mental Training Program to Increase your Leadership Performance by Dr. Jason Selk published by McGraw Hill. Why am I adding this to my blog site?  My objective in addressing sales leadership issues is to provide you ideas, tools and concepts to increase your professionalism. like to read a business book focused on some aspect of my profession, then I will switch to another form of book for personal fun. believe your sales teams and you should have a personal development plan. This section pays for the book!