Marrin Costello is an American businesswoman, designer, and brand-architect.

Her entrepreneurial journey began at age 10 after falling in love with the art of jewelry making. Just two decades later, Costello has built a luxury lifestyle brand that has been featured in Vogue, Huffington Post, and Who What Wear, amongst many others — and whose collection can be found in over 100 retailers nationwide. The byproduct to creating a successful company and internationally recognized business? Having the experience, knowledge, and foundation to support other companies, brands, and entrepreneurs alike in finding their own respective success.

Costello harmoniously bridges creativity and finance in helping build beautiful, sustainable, and profitable companies — with purpose.

Now a consultant to companies worldwide, Costello has been named a brand architect — offering perspective, facilitating clarity, and delivering results to clients across all fields of expertise. The MARRIN COSTELLO INC ® approach is holistic in both concept and practice — building both consistency and momentum for clients to withstand the varying seasons of business, entrepreneurship, and life.

While the MC INC team is currently headquartered in Los Angeles, Costello travels the globe connecting with the MC community, building lasting relationships with clients, and collaborating with other like minded thought leaders and brands. Through excellence and transparency — MARRIN COSTELLO INC is centered on a mission to deliver results and exceed customer expectations.

Whether adorning clients with jewelry or helping companies thrive, the core of the MC INC brand at large is being of service to others and making people feel fabulous. My mission is to facilitate the creation of lasting brands where the company vision, aesthetic, and financials align. 

Successful jewelry brand to business consultant — why pivot?

There are so many coaches and consultants — what makes you different?

I’ve been in your position. I’ve done the legwork. I know what a brand needs and I know what developing, maintaining, and growing a successful business takes. We approach companies from all angles — so that the brand is strong and the branding maps to sales. Ultimately, without sales you don’t have a business — you have a hobby.

Have you ever worked with consultants?

I’ve worked separately with both branding and financial consultants alike — but have never had an experience where those two components were harmoniously merged. There is a large, much-needed white space for MC INC’s consulting service — and I know from personal experience how to successfully blend both brand and finance to achieve lasting results.

Overpromise and overdeliver — Every. Single. Time. I go above and beyond for all of my clients, and care for their businesses as if they were my own.

Just as every client is unique, each MC INC experience is completely customized. There is no one-size-fits-all formula.

It is important that every client feels both seen and heard — and that they know the consulting service they are receiving is tailored completely [and strategically] to them.

What is your consulting strategy?



With the holistic MC consulting process, no stone is left unturned.