Dorothy was raised just south of Lincoln by parents who were both competitive shooters so she is no stranger to firearms. She tagged along with her parents on the competition circuit for years before leaving home and pursuing a career in nursing while raising a family. When she decided to get her concealed carry permit in 2013, her passion for shooting was reignited and she began the process of becoming an instructor. Since then, she has obtained all of the available credentials for NRA instructors as well as becoming an NRA Counselor. She is currently the only active female counselor in the area and has grown to be one of the top instructors in Nebraska. Dorothy even accomplished the level of Distinguished Expert in the Front Sight Defensive Handgun course and graduated at the top level in her John Farnam Defensive handgun class.
In 2017 she married Justin Grusing who is also an NRA counselor and together they lead the Nebraska Shooters team. They both strongly believe that they are occasionally instructors, but always students and never miss an opportunity to attend classes and seminars to keep themselves informed.
Recent training for Dorothy Grusing:
| Date | Trainer | Course | Hours |
| Jan 16-19, 2017 | Front Sight | Defensive Handgun | 40 |
| March 3-6, 2017 | Front Sight | Defensive Handgun | 40 |
| Jan 13, 2018 | Brookside | Tac-Med | 8 |
| Jan 14, 2018 | Brent Craft | Threat Pattern Recognition | 5 |
| May 18-20, 2018 | John Farnam | Defensive Pistol | 20 |
| May 31-June 3, 2018 | Massad Ayoob | MAG-40 | 40 |
| November 24, 2018 | US Lawshield | Gun Shot Wound First Aid | 4 |
| Dec 28, 2018 | US Lawshield | Gun Law Seminar | 3 |
| March 9, 2019 | Dr. William Aprill | Inside the Criminal Mind | 9 |
| July 27, 2019 | Dave Spaulding | Combative Handgun | 9 |
| September 28/29, 2019 | Dayle Hammock | NRA CCW Instructor | 32 |
| November 15, 2019 | Dick Clark | Laws of Concealed Carry and Interstate Travel | 4 |
| March 6-9, 2020 | Front Sight | Defensive Pistol | 40 |
| June 6, 2020 | Norm Hood | Thunder Ranch Condensed Advanced Pistol | 8 |
| June 7, 2020 | Norm Hood | Thunder Ranch Condensed Shotgun | 8 |
| March 5-8, 2021 | Front Sight | Defensive Pistol | 40 |
| Sept 9-12, 2021 | Massad Ayoob | MAG-40 | 40 |
| Sept 9, 2021 | Norm Hood | Thunder Ranch Condensed Urban Rifle | 8 |