Navigate Family Transitions With Steady Legal Support
Your family's future deserves guidance rooted in experience and clarity at every step.
Secure Your Family's Legal Foundation
Practical guidance backed by experience across Oregon's family and estate law
When life shifts—whether through separation, the need to protect a vulnerable loved one, or planning for the future—Mastanduno Law Group helps families across the Portland area address what comes next. We represent clients navigating family law, guardianship and conservatorship matters, estate planning, and probate with care and focus.
You'll know what to expect as your case moves forward. We walk you through the steps involved, answer questions as they arise, and help you understand how Oregon law applies to your situation. Phone consultations are available to discuss your circumstances before moving ahead.
Our team brings more than 20 years of combined experience to sensitive legal matters that affect your family's security and well-being. Mastanduno Law Group serves clients throughout Multnomah, Washington, Clackamas, Columbia, Tillamook, Hood River, Marion, Yamhill, Linn, Polk, and Wasco counties, offering representation across a range of related legal needs so you don't have to piece together multiple firms as your situation evolves.
Contact our office to schedule an over-the-phone consultation with one of our attorneys.
Practice Areas
Family Law
Divorce
Guardianship & Conservatorship
Trusts
Build Security Through Thoughtful Estate Planning
Protect the people who matter most with planning that reflects your values and goals.
How We Approach Your Case
From the first consultation, you'll have a sense of what lies ahead and how we'll work together.
We explain the legal process in plain terms, outline realistic timelines, and keep you informed as decisions are made and documents are prepared. You're not left wondering where things stand or what happens next.
Whether you're addressing custody arrangements, dividing complex property, establishing a guardianship, or administering an estate, we help you understand your options and the implications of each choice. Our role is to provide dependable counsel while respecting the personal nature of the decisions you're making.
Our representation spans a wide array of services designed to meet evolving family needs:
Divorce and modifications that account for changing circumstances, nontraditional family structures, and the distinction between child custody and parenting time under Oregon law
Guardianship and conservatorship proceedings for both adults and children when legal authority is needed to protect someone's welfare or finances
Estate planning tools including wills, trusts, and powers of attorney that reflect your intentions and comply with state requirements
Probate and estate administration services for families settling an estate or navigating will contests in the greater Portland metro area
Why Families Choose Mastanduno Law Group
Mastanduno Law Group has built its practice on representing clients through some of the most personal and challenging moments they'll face. Based in Portland, we've developed a deep familiarity with the courts, procedures, and legal landscape across the Oregon counties we serve.
Our attorneys bring a steady, professional presence to cases involving family transitions, protective proceedings, and estate matters. We handle each case with integrity and attention to detail, ensuring that paperwork is thorough, deadlines are met, and your interests are represented with care. You can rely on us to be responsive, prepared, and committed to achieving outcomes that serve your family's long-term well-being.
Areas We Serve
List of Services
Steven Mastanduno
Partner
With over a decade of legal experience, Steven Mastanduno focuses his legal practice on family law, estate planning, and probate law, including estate administration and protective proceedings like guardianships and conservatorships, while also consulting on business and contract issues.
He understands that every family goes through change and has its own goals, and when the legal system is involved, these changes can be challenging. This is even more true when it to comes to non-traditional and blended families. Steven will strive to make these life changes as smooth as possible for you and your family, and to help plan for what the future may bring. His focus is on resolving disputes without the need to litigate, but he is a capable litigator and can skillfully represent you in court. Steven is a qualified mediator and is happy to assist with guiding you towards agreements that make litigation unnecessary. He earned his J.D. from Willamette University College of Law in Salem, Oregon, with a certificate in dispute resolution.
Nathan Jones
Partner
Nate Jones believes that through better communication, people are more able to resolve their conflicts in a long term and sustainable manner. He focuses primarily on divorce, custody, and protective orders, with an understanding of how these complex legal situations can affect people’s lives on every level. He is an advocate for victims of domestic violence and believes in standing up for those who society has left behind. His focus is on resolving issues through alternative dispute resolutions; however, he has the experience and drive necessary to zealously litigate on your behalf. He earned his J.D. from Willamette University College of Law and resides in Portland.
Carmel Swanson
Legal Assistant
After working with the public for over 14 years, Carmel Swanson has established true empathy and patience for people from all walks of life. As a legal assistant, she is
dedicated to making sure you are heard, taken seriously, and will lead you in the direction that is best suited for your needs. On top of setting you up with either Steven Mastanduno or Nate Jones for a consultation appointment, she will also lend an ear and listen to your worries in order to provide some calming relief towards the next steps in your case. She understands that family matters are sensitive, stressful, and sometimes heartbreaking. If she finds that you need other resources for your case, she is more than willing to provide you with information that she has carefully researched because everyone deserves justice.
Carmel is a true Oregonian, growing up in the beautiful wine country region of Yamhill county. She has touched many avenues of work life including the culinary arts and is also a
licensed esthetician (if you ever need skincare advice, she’s your girl!). She currently resides with her mother, Sherry, and their two cats, Oliver and Willow. When she is not preoccupied with work, she enjoys painting, karaoke, live music, theater, and spending time with her beloved friends.
Cosmo Mastanduno
Puppy at Law
Filling out our legal team is Cosmo, Steven’s dog and our firm’s youngest member. Cosmo was born in 2025 and has been with the firm since then, quickly rising through the ranks and establishing himself as our firm’s greatest morale booster. Cosmo brings equal parts charm, curiosity, and playfulness, and takes his responsibilities very seriously. When not supervising our firm, Cosmo can be found jumping up on visitors, offering his emotional support, and conducting important patrols for head rubs and treats. With bright eyes, perky ears, and a knack for stealing hearts in record time, Cosmo has quickly become one of our favorite colleagues. Outside of the office, Cosmo enjoys long neighborhood walks, cozy naps, and skittering on hard wood floors.
The Guidance You Deserve
Honest
We know you value honesty in an attorney. Complex issues like family and estate planning require transparency and communication. Our direct and honest style strives to find favorable outcomes for you.
Knowledgeable
As attorneys, we are experienced in family law, estate planning, and guardianships and strive to offer you informed advice in your most challenging moments. We serve the Portland Metro area, from Gresham to Beaverton to Oregon City.
Approachable
We understand the importance of straightforward and accessible communication. We are a small firm which allows us to give you the individual attention you need.
Success with our clients in mind
Read some of our featured reviews or see all our success stories on our testimonials page!
