Skip to main content

Stephen Isaac Gassner

Divorce and separation Attorney at Upland, CA

4.9   7 reviews

also known as Law Office of Stephen Gassner, APC, Certified Family Law Specialist

Virtual consultation available
Virtual consultation available
  • Licensed for 28 years
    State CA
    Acquired 1995
    Active No misconduct found

We have not found any instances of professional misconduct for this lawyer.

About Stephen

Learn Stephen’s areas of practice.

Practice areas
  1. Divorce and separation
    How can a marriage of 20-years or miore divorce? It happens. Lives are intertwined with kids of different ages, supporting two residences on an aggregate income that's enough for only one. Family business has to be controlled by only one spouse (or it gets destroyed. Who will live in the family residence? Must it be sold? Do we have to avoid foreclosure? What about the pension that has been accumulating over the years? How can we get through this and still be friends?

    28 years

  2. Child custody
    Mr. Gassner has a BA in Psychology from before he attended Law School. He has years of experience at reviewing, using, attacking, and expert clarifying psychological reports. High conflict child custody cases present difficult but solvable problems, and we address them eagerly.

    28 years

  3. Domestic violence
    Whether you are an alleged victim or perpetrator, the court is a risky place to be. Knowing the laws and the legal standards to be proved, is everything. Folks seldom understand their risks going in. They frequently feel they have to win, because they just need to show the evidence... until somebody on the other side says "objection" and their evidence becomes inadmissible - and the court won't consider it. Having a lawyer is everything in these situations.

    28 years

  4. Child support
    Of course there is a statewide guideline formula, and any fool can run the numbers. But what numbers go into the formula? What is your strategy to collect your arrears? Or to keep something after a huge order has been made against you? Get a consultation to help figure that out.

    28 years

  5. Family
    Practice includes Divorce, Paternity, Property Management and Control, identification, classification and division of property and debts, Child Custody and Visitation, Division of Income (e.g. Child Support, Spousal Support and Deferred Compensation), and protection from Domestic Violence. Often involves mediation rather than litigation; often requires clarification of difficult issues.

    28 years


Growing up in the Gassner family meant learning Family Law from the gurus. With 25+ years of experience as a licensed attorney, Mr. Gassner has seen and managed practically every sort of family law matter that ever arises. If you think you have a complicated family law issue, then Mr. Gassner can probably simplify it. We handle business valuation, management and control of property and debt during a divorce, domestic violence, child support, spousal support, child custody, joint child custody sharing arrangements, mediation, cross-jurisdictional matters, all other aspects of California Family child custody to enforcement (and defense) of child and spousal support. We are well configured for complex family law matters, though we also handle simple ones efficiently. Mr. Gassner has the immediate encyclopedic knowledge and ability to provide specific answer questions about practically all substantive, procedural, and practical issues in California Family Law.


AV Preeminent Peer Review Rating
Client's Choice 2019
Client's Choice
Top Contributor 2019,2017,2016,2015
Top Contributor
2019 2017 2016 + 1 ...

Photos and videos

Contact Stephen

Law Office of Stephen Gassner


4.9 / 5.0
  7 customer reviews
5 Star
4 Star
3 Star
2 Star
1 Star
Client's Choice 2019
Client's Choice
Client's Choice is an Avvo award granted to attorneys with a significant number of client reviews over 4 stars in a given year.
Posted by Linda | August 14, 2019
This review is from a person who hired this attorney.
| Hired Attorney
Representation at its BEST!
I retained the services of Mr. Gassner after unsatisfactory success with two other attorneys. He took the reigns with little time to prepared for trial. I was very impressed with his ability to familiarize himself with my case. He made every effort to be available to work with me to prepare. My interactions with him have shown me that he is passionate about his work and clients. Never rushed, he has always taken the time to explain my options and his opinions. He has superior knowledge of family law and is well respected in the courtroom. We are only halfway through the divorce proceedings and the outcomes for me since I hired Mr. Gassner have been in my favor. I am absolutely certain that I couldn’t have picked a better attorney to represent me. I feel confident that he will continue to go above and beyond to represent me for the remaining part of the proceedings. My only wish is that I would have retained him from the beginning.
Read less
Posted by Martin | December 1, 2019
This review is from a person who hired this attorney.
| Hired Attorney
Great lawyer with a deep knowledgable in domestic and international law
I hired Stephen to help me with a highly complex international custody case. His inherent knowledge of the law, both domestic and international, his awareness and sensitivity of the situation, helped to not only enlighten me, but also the opposing lawyer and most importantly, the judge. Stephen made sure the rights of the children were protected and put in effect. He is a great negotiator. Today, the children are better off because of him and the parents are talking to each other again. Without Stephen's skill set, our situation could've ended in a disaster. Therefore, I can only recommend Stephen to anyone dealing with a complex situation or where communication between parents has come to a halt. If you're looking for a lawyer with integrity whose main concern is upholding the law, Stephen Gassner is the right person for you.
Read less
Posted by Lilia Guzman-Motz | October 26, 2019
This review is from a person who hired this attorney.
| Hired Attorney
Great lawyer
Steven is fair and just lawyer and also ruthless Steven gives his best to win the case. He was an awesome divorce lawyer not to have my best interest at heart. When he needed to be tough he was tough and ruthless but fair with the other side. Steven won my case and I was very appreciative of him through the process of the divorce. Direct and straight forward with heart.
Read less
Posted by Joseph Hanna | June 25, 2019
This review is from a person who hired this attorney.
| Hired Attorney
Very honest, know what he is doing i recomnd him
i think i have to write pages and pages about Mr. Gassner he help from his heart, answer your question , he goes to the court with full knowledge of facts and everything, very quit tell and speaks the truth only , every one respect him , he help me with my custody case after i got exhausted with three different lawyers
Posted by Olivia | March 12, 2015
I'm so happy
I'm very grateful and impressed for Stephen for his kindness integrity and professional knowledge concerning family law. He was incredibly resourceful.
Posted by Star | March 25, 2013
Mr Gassner is trustworthy and has a great amount of integrity. I highly recommend him, and am confident that he will handle any case with the utmost sensitivity and honesty.
Posted by TOMMY | October 28, 2019
This review is from a person who hired this attorney.
| Hired Attorney
View less reviews


  • Hourly Rates $ 175-450 per hour
  • Retainer Sometimes
Payment methods
Cash, Check, Credit Card


AVVO RATING 10.0 (Superb)

Work Experience

  • Founder/Owner/Family Law Trial Attorney
  • Law Office of Stephen Gassner
  • 2012 - Present
  • Trial Attorney
  • Law Office of Marc Grossman
  • 2011 - 2012
  • Trial Attorney
  • Gassner & Gassner
  • 1999 - 2011


  • Claremont Graduate University
  • Master of Information Systems
  • 1997
  • University of La Verne College of Law
  • Juris Doctor
  • 1994
  • National University
  • Master of Business Administration
  • 1989
  • Pitzer College (Claremont)
  • BA - Bachelor of Arts
  • 1984
View all education


  • State Bar of California, Law Practice Management and Technology Section
  • Board of Directors
  • 2001 - 2004
  • California Young Lawyers Association
  • Board of Directors
  • 1996 - 1999
  • California Young Lawyers Association, Technology Subcommittee Chair
  • Chair
  • 1996 - 1999

Languages Spoken

  • English

Honors and Awards

  • Certified Specialist
  • State Bar of California
  • 2019
  • Peer Review Rated
  • Martindale-Hubbell
  • 2016

Attorney endorsements

Received (10)
Given (2)
Endorse Stephen
Family Attorney | Oct 06
Relationship: Fellow lawyer in community
"Stephen is a well-mannered, highly versed family law attorney. He goes above and beyond what it takes to practice law. Above all I find him very companionate. He has the respect and admiration of his peers and judicial officers alike. I would not hesitate to recommend him to anyone facing a family law issue."
Divorce and separation Attorney | Sep 21
Relationship: Other
"I endorse this lawyer."
Unknown Attorney | Mar 04
Relationship: Fellow lawyer in community
"Top-notch attorney. Highly respected in the legal community."
Family Attorney | Nov 10
Relationship: Fellow lawyer in community
"I endorse this lawyer."
Family Attorney | Jun 05
Relationship: Fellow lawyer in community
"I endorse Stephen. He is a highly skilled attorney that is well respected in the legal community."
Family Attorney | Sep 10
Relationship: Fellow lawyer in community
"I endorse this lawyer. I took over for Mr. Gassner on a contested dissolution proceeding and he was invaluable in helping me get caught up on all the issues on the case. He was extremely knowledgeable and friendly and definitely had the client's best interest in mind."
Litigation Attorney | Jan 10
Relationship: Worked together on matter
"I endorse this lawyer."
Domestic violence Attorney | Apr 25
Relationship: Fellow lawyer in community
"Steve has his specialties, but has pretty much seen it all. I endorse him."
Family Attorney | Apr 20
Relationship: Fellow lawyer in community
"I endorse this lawyer. When he takes on a case, Stephen doesn't rest until the battle is done."
Family Attorney | Apr 20
Relationship: Fellow lawyer in community
"I endorse this lawyer. Steve is a real professional, and his overall knowledge of the law allows him to assist in most any situation."
View more endorsements
Divorce and separation
Personal injury
Upland Divorce and separation Lawyer Stephen Isaac Gassner
Stephen Isaac Gassner
Divorce and separation Attorney
Upland, CA
Licensed for 28 years
Virtual consultation available