Randy co-authored the Courageous novel and The Resolution for Men with Alex and Stephen Kendrick. The novel, which was based on the Courageous movie screenplay by the Kendrick brothers, tells the story of law enforcement officers Adam Mitchell, Nathan Hayes, and their partners as they face a challenge that none of them are truly prepared to tackle: fatherhood. The Resolution for Men challenges men of all ages to become as bold and intentional about embracing their responsibilities as leaders of their homes, marriages, and children.

He also co-authored Women Under Stress (now out of print) with his wife Nanci, and wrote The Ishbane Conspiracy with his daughters Karina and Angela the summer before both of them got married.

Randy has this to say about writing with his daughters: "My daughters Angela and Karina helped me write this book. It was my first collaboration since writing a book with my wife Nanci fifteen years prior, and it was a joy. The summer before they both got married I thought it would be great if they weren't working jobs that pulled the family apart. The book idea seemed a great way to do it. I asked them if they wanted to spend a summer writing a book with their dad. They said yes, and I'll always be glad.

"I can't think of two people more qualified and skilled, in both the spiritual and artistic senses, I could have worked with. We read and discussed books on fiction writing, brainstormed characters and plots, stimulated each other's thinking, prayed together, had lots of fun and shared the frustrations and mind-numbing hard work of disciplined writing. Angela and Karina are true co-authors, not token ones. This is their book as much as it's mine, and they have my deepest respect."