As part of my job, I travel a lot. Business travel is rewarding and certainly necessary, but the layovers, flight delays and transfers mean a lot of time spent in transit.

I take these opportunities to continue my education by reading, as I truly believe the best salespeople never stop learning. Specifically, reading books about leadership, business best practices and high-level sales strategies keep me sharp and give me new ideas. If you travel often and are looking to expand your own repertoire, here are my top five sales books to make your business trip personally productive.

1. Heavy Hitter IT Sales Strategy by Steve W. Martin--I have been lucky enough to know and collaborate with Steve for several years. He's a professor, Harvard Business Review author and one of the most insightful students of sales I know. This book is an unrivalled resource for senior salespeople who want to improve their strategy for winning highly competitive accounts. What really sets the book apart is its impeccable research. The findings and recommendations are drawn from detailed interviews with over a thousand of the most successful sales executives and leaders in the world. It's like having access to thousands of the best minds in technology sales at once.

2. Agile Selling: Get Up to Speed Quickly in Today's Ever-Changing Sales World by Jill Konrath--I started following Konrath after reading her book Snap Selling and have consistently found her strategic, process-driven approach to be extremely well thought out. Salespeople move quickly and are consistently being forced to contend with new information. Konrath's tactics, unlike more traditional methods, were developed specifically for coping with that breakneck environment. Anyone selling in a competitive environment would benefit from her tips for nimble, effective sales.

3. The Ultimate Question 2.0 by Fred Reichheld--I am a big believer that the customer experience journey starts in sales. Although this is a book aimed at customer success rather than pure sales, it is one that I recommend every salesperson reads. The book is centered around a single metric (Net Promoter Score) that tells you all you need to know about whether the quality of your customer journey is helping your company grow or working against you. I've seen the Net Promoter Score practices described in this book used in a variety of organizations, and each time it has been the single most important factor in helping those companies emerge as the leader in their space. In fact, my entire sales organization at Velocify is structured around this framework and it has helped us achieve astounding results.

4. Crucial Conversations: Tools for Talking When Stakes Are High by Kerry Patterson, Joseph Grenny, Ron McMillan, Al Switzler--Again, this book isn't sales–specific, but it's absolutely sales–essential. As salespeople, we have to be continuously willing to have hard conversations with our prospects in order to get them out of their comfort zone, and as sales leaders we need to be good at having meaningful conversations with team members. This book addresses how to manage high-stakes conversations, which can be emotional, complicated and difficult to navigate.

5. The Little Red Book of Sales by Jeffrey Gittomer -- The Little Red Book of Sales is a classic, pure and simple. I recommend every salesperson read this book, if only to better understand what traits make for a good sales professional. It's a great way to get motivated and remind yourself what really matters. I'd especially recommend it to new reps looking to become better–versed in the language of the field.

As someone who's been working in sales for decades, I'm consistently astonished by how much more there is to consider. Whether you're on a plane, in an airport terminal, or in your hotel, these books will make your next business trip a learning experience.