Experience

Makes all the difference

We are here to provide quality strategies customized to your needs–and to be your primary source of financial advice. We concentrate on developing long-term relationships through a commitment to quality client service. You can rely on our personalized advice, first-class solutions, and extensive wealth management experience.

Timothy W. O'Brien

Managing Director–Wealth Management

With over four decades in the financial services industry, Tim has built his career on trust, integrity, and exceptional client care—values proven not just in words but in action, reflected in client relationships that span decades, reaching back to his earliest days at EF Hutton in 1983. He learned the business from the ground up and quickly earned a reputation for his relentless work ethic—a commitment that continues to define his practice today.

Tim went on to join PaineWebber in 1990 and later served as Branch Manager of the South Burlington, Vermont office from 1995 to 2001. In 2008, he earned the firm’s Wealth Advisor designation, underscoring his dedication to delivering thoughtful, personalized strategies. A testament to his continued excellence, Tim has been recognized on the Barron’s Top 1,200 Financial Advisors list every year since 2010.

He anticipates client needs, delivers clear strategies, and is fully present throughout each step of their financial journey. Inspired by Vince Lombardi’s words that “the dictionary is the only place where success comes before work,” Tim lives by that philosophy, working each day so his clients can move forward with confidence, protect their wealth, and preserve their legacies for generations to come.

Tim has a long history of community involvement, including his years of support for the Boys & Girls Club. Today, he also enjoys supporting his wife Jodie’s small business, DUET, especially through its partnership with the IDDeal Foundation, which creates meaningful employment opportunities for adults with intellectual and developmental disabilities.

Outside of work, Tim and Jodie share a love of travel, golf, and skiing, and they especially cherish time spent with their children and grandchildren.

Registered States:
  • AL
  • AZ
  • CA
  • CO
  • CT
  • DC
  • FL
  • GA
  • IL
  • KS
  • MA
  • MD
  • ME
  • MI
  • NC
  • NH
  • NJ
  • NM
  • NY
  • OH
  • OK
  • OR
  • PA
  • RI
  • SC
  • TN
  • TX
  • VA
  • VT
  • WA
  • WV
  • WY

Recognized as an industry leader:

  • Barron's Top 1,000 Financial Advisors, 2011, 2012, 2013The Barron's rating is awarded annually in March and is based on information from the prior year Q3. 
  • Barron's Top 1,200 Financial Advisors, 2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022, 2023, 2024, 2025
    The Barron's rating is awarded annually in March and is based on information from the prior year Q3. 
  • Forbes Best-in-State Wealth Advisors, 2024, 2025The Forbes rating is compiled by Shook Research and awarded annually in April based on information from a 12 month period ending June of the prior year.

Eligibility is based on quantitative factors and is not necessarily related to the quality of the investment advice. For more information on third party rating methodologies, please visit ubs.com/us/en/designation-disclosures

Education

  • University of Vermont, Bachelor of Science - Economics

Credentials

  • Wealth Advisor
38 Eastwood Drive
Suite 400
South Burlington, VT 05403

Email Me

timothy.obrien3@ubs.com,jennifer.mcgrath@ubs.com,stefanie.gretkowski@ubs.com
Timothy W. O'Brien
38 Eastwood Drive,South Burlington,VT,05403

Stefanie C. Gretkowski, CFP, CDFA

Senior Wealth Strategy Associate

Certified Divorce Financial Analyst

Experience

  • 26 years of experience in the insurance and financial service industry
  • Stefanie started at Prudential Insurance in 1997 and joined PaineWebber Inc. in 1998
  • In 2000 to 2003 she joined Smith Barney and then rejoined UBS Financial Services in 2003
  • In 2013 Stefanie obtained her CERTIFIED FINANCIAL PLANNER® certification and is CFP® professional

Degree

  • Master of Business Administration, Champlain College, Burlington, Vermont
  • Bachelor of Arts – Professional Studies, focus in business, Johnson State College

 

Registered States:
  • AZ
  • CA
  • CT
  • FL
  • IA
  • IN
  • KS
  • MA
  • ME
  • MI
  • MT
  • NC
  • NH
  • NJ
  • NY
  • OR
  • SC
  • TX
  • VA
  • VT
  • WA

Education

  • Champlain College, Master of Business Administration
  • Johnson State College, Bachelor of Arts – Professional Studies, Focus in Business

Credentials

  • Certified Divorce Financial Analyst
  • CERTIFIED FINANCIAL PLANNER
38 Eastwood Drive
Suite 400
South Burlington, VT 05403

Email Me

stefanie.gretkowski@ubs.com
Stefanie C. Gretkowski, CFP, CDFA
38 Eastwood Drive,South Burlington,VT,05403

Jennifer Christoffel McGrath

Senior Registered Client Associate

Experience:

Jennifer joined the firm, formerly, PaineWebber in 1994.  She worked with Tim and his Branch Management Team until she left to raise her three boys.  She returned to the O'Brien Gretkowski Team in 2014.  She is a Senior Registered Client Associate with 20 years experience in the Financial Services Industry.

Degree:

Bachelor of Arts - Business Administration 1998, Champlain College, Burlington, VT

Personal:

Played 2 years, Soccer and Softball at the Collegiate level.  She loves to play golf with her family.  She enjoys watching her boys play baseball, from Little League right up through the Collegiate Level.

Registered States:
  • AK
  • AL
  • AZ
  • CA
  • CO
  • CT
  • DC
  • DE
  • FL
  • GA
  • IA
  • IL
  • IN
  • KY
  • MA
  • MD
  • ME
  • MI
  • MT
  • NC
  • NH
  • NJ
  • NM
  • NV
  • NY
  • OH
  • OR
  • PA
  • RI
  • SC
  • TN
  • TX
  • UT
  • VA
  • VT
  • WA
  • WY

Education

  • Champlain College, Burlington, VT, Bachelor of Arts - Business Administration

Credentials

  • Senior Registered Client Associate
38 Eastwood Drive
Suite 400
South Burlington, VT 05403

Email Me

jennifer.mcgrath@ubs.com
Jennifer Christoffel McGrath
38 Eastwood Drive,South Burlington,VT,05403

Joseph Dieterle

Senior Wealth Strategy Associate

CERTIFIED FINANCIAL PLANNER

Experience      

Jake's first experience with UBS was an internship during summer in college at our Portland, ME branch. After graduating from Trinity college he moved to New York City to join UBS in the Financial Advisor Development Program. Upon graduating from the Development Program he worked in the firm’s Institutional Advisory Group for four years during which time he obtained his CERTIFIED FINANCIAL PLANNER™ certification. In that role he was a Financial Advisor and Corporate Stock Benefit Consultant working with Directors and Executives of the firm’s corporate clients in the equity award space. He moved to the South Burlington Branch in 2024.

 

Degree

  • Bachelor of Arts – Economics, Trinity College
  • Minor in Formal Organizations, Fast Track in Entrepreneurial Studies, Trinity College
  • Tuck Business Bridge Program at Dartmouth

 

Personal

  • Jake was on the Track and Field team at Trinity for four years.
  • Jake enjoys golfing, fishing and most things outdoors. 
  • He lives in South Burlington with his wife, Eliza.

 

 

Registered States:
  • AK
  • AL
  • AR
  • AZ
  • CA
  • CO
  • CT
  • DC
  • DE
  • FL
  • GA
  • HI
  • IA
  • ID
  • IL
  • IN
  • KS
  • KY
  • LA
  • MA
  • MD
  • ME
  • MI
  • MN
  • MO
  • MS
  • MT
  • NC
  • ND
  • NE
  • NH
  • NJ
  • NM
  • NV
  • NY
  • OH
  • OK
  • OR
  • PA
  • PR
  • RI
  • SC
  • SD
  • TN
  • TX
  • UT
  • VA
  • VI
  • VT
  • WA
  • WI
  • WV
  • WY

Education

  • Trinity College, Bachelor of Arts – Economics
  • Dartmouth College, Tuck Business Bridge Program

Credentials

  • CERTIFIED FINANCIAL PLANNER
38 Eastwood Drive
Suite 400
South Burlington, VT 05403

Email Me

joseph.dieterleiv@ubs.com
Joseph Dieterle
38 Eastwood Drive,South Burlington,VT,05403

This website uses cookies to make sure you get the best experience on our website. You can find more information under the Privacy Statement. You are free to change your cookies' settings in the privacy settings.

Go to privacy settings