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Boulder, Colorado


Schooling and Show Apparel for Jumpers and Dressage Riders, Meticulously Tailored Equestrian Styles using Cutting-Edge Technologies Posh Performance!

Where we live?

Boulder, Colorado USA - Land of Great Skiing, Riding and Cycling. Our Ponies love the Mountain air and 300 plus days of sunshine!

Blending Posh with Performance, Mastermind Equestrian Apparel offers a generous helping of European tradition with Cutting Edge innovation and American Ingenuity. Imported and featuring Swiss Schoeller (R) Fabric Technologies, German Gutos Snaps and Fittings, and Genuine Leather with LYCRA (R) full seats to keep your Ride Elegant, Energized, Clean and Secure.





Understated elegance meets American grit. Posh meets performance. Our iconoclastic designs are meticulously constructed of Swiss Schoeller smart fabric technology that maintains the harmonic balance between aesthetics, fashion and functionality.

Ride with unbridled panache. Ride Mastermind


Meet Mandy Porter

When describing a person that exudes such talent, dedication, and passion for their craft it can be tempting to rely on cliché adjectives and hyperbole; however, in the case of Mandy Porter, even these somehow fail to adequately capture her unbridled (no pun intended) devotion to and enthusiasm for the world of Grand Prix Show Jumping.

Mandy, a Northern California native, exhibited an innate acumen for working with horses early on. While working toward obtaining her degrees in both animal science and agricultural business management from Cal Poly (San Luis Obispo), Mandy decided to devote herself entirely to pursuing a career as a professional competitive show jumper. She quickly rose up the ranks: from juniors, to amateurs and, eventually, found herself competing at the Grand Prix level.

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Upon graduation, Mandy was offered a position at Gerhard Etter’s dealing barn in Muntschemier, Switzerland; which proved to be an invaluable opportunity that largely helped shape her approach to both riding and training. In conjunction with her career as a professional jumper, in 2001 Mandy founded ACP Enterprises, Inc.– located in the equestrian hub of Del Mar, California– where she oversees every aspect of the facility.

Throughout the course of her illustrious career as a professional show jumper, Mandy has had the honor of working with some of the most elite horses and renowned names in the equestrian world. As she acknowledges: “I’ve had great opportunities meeting some great people, the owners, but it’s really the horses that have enabled it all.” Among her numerous achievements, some noteworthy moments include: Mandy’s 2017 triumph in the prestigious Coachella HITS AIG Million, competing on three Nations Cup teams internationally in Austria, France, and Spain, and her recent victory at the $60,000 KindredBio Grand Prix Temecula Valley Horse Show earlier this year.

Yet, despite such an impressive string of successes, Mandy is not one to rest on her laurels. Instead, she continually strives to improve: “It’s not all about winning. It’s how you do everything– when you don’t win, and what you do after that, that makes you who you are.” It is this unique combination of professionalism, humility, talent, and drive that establishes Mandy amongst the highest echelon of show jumpers on today’s circuit.