The Garden City Center Building
100 Quentin Roosevelt Boulevard
Garden City, NY 11530

A Premier Divorce And Family Law Firm.


A Premier Divorce And Family Law Firm.


Family Law

Family law is an extremely emotional practice area and encompasses a wide variety of issues.

Long Island's Premier Divorce and Family Law Attorneys

Our Commitment

At The Law Offices of Seidner & Associates, PC, we understand that when you’re going through a significant life change – be it a divorce, child custody issues, or any other family law matter – you deserve a legal team that doesn’t just see you as another case number.

We see your unique needs, your concerns, and the hopes you have for your future. We understand that you’re not just looking for an experienced family law attorney, but a steadfast advocate, someone who can help you make sense of the complicated legal system with unwavering focus.

Our attorneys approach every case with a singular commitment: to treat every client as we would want to be treated. Whether you are dealing with a contested divorce or an uncontested one, seeking an order of protection, modifying child custody arrangements, navigating same-sex family law issues, or advocating for father’s, mother’s or grandparents’ rights, we are here to stand by your side. We don’t just work for you, we work with you, ensuring you are informed about every aspect of your case.

This commitment sets us apart from others. Here, you are not another file on a shelf. You’re a person deserving of respect, empathy, and a focused legal team that will stop at nothing to protect your rights and your future.

The Matrimonial/Family Law Attorneys You Can Trust

Clients across Long Island trust our family law practice because of our relentless pursuit of justice and a proven record of successful outcomes in a wide range of divorce and family law matters. These include:

  • High Net Worth Divorces: With an eagle eye for detail, we handle the complexities of substantial estates, guarding your wealth and your future.

  • Child Custody and Visitation: We are determined to protect your rights and the best interests of your children, no matter how complex your custody matter may be.

  • Spousal & Child Support: In addition to ensuring you get or pay a fair amount; we make sure it reflects your life’s reality, so your financial health remains protected.

  • Property Distribution: We are your advocates in ensuring a fair division, one that respects your contributions and safeguards your entitlements.

  • Business Valuation: We are meticulous in assessing business assets and uncovering any hidden assets, so that both parties receive an accurate valuation. 

  • Post-Judgment Modifications: We are here to help amend court orders, reflecting new circumstances like income changes, relocation, or changes in your child’s needs.

  • Prenuptial Agreements: We believe in love, and we also believe in a well-prepared future. We create prenups that honor both.

  • Uncontested Divorce Filings: When things are amicable, we ensure a swift, respectful resolution that enables you to start your new chapter sooner.

  • Contested Divorces: When negotiation seems impossible, our tenacious advocacy ensures your rights and interests are fiercely defended. From contentious asset division to child custody cases, we strive to turn the tide in your favor.

Why Choose Us

Unmatched Legal Skills, Experience and Resources

With a combined experience of nearly five decades, our team has honed its skills in matrimonial and family law to razor-sharp precision. Our track record of successful cases, both inside and outside the courtroom, stands as testament to our legal prowess. Our name carries weight, and we have extensive resources and a strong network of experts, providing you with a powerful ally in your corner.

We are Big Enough to Fight, Small Enough to Care

Our firm is just the right size, striking the perfect balance between having the capacity to handle complex legal matters and maintaining intimate relationships with all of our clients. With us, you’re never just another client. We focus on your unique circumstances.

A Respected Leader in the Field

Our founder, Matthew S. Seidner, Esq., is regarded as one of the most respected attorneys on Long Island, New York. Armed with extensive knowledge and a formidable reputation, he is a master negotiator who is unyielding in his commitment to championing for his clients. 

We are More Than Just Lawyers – We are Your Allies in Adversity

When you’re faced with tough decisions involving family, remember, you’re not alone. Choosing us at The Law Offices of Seidner & Associates, PC, means choosing a partner who will fight fiercely for you, and always keep your best interests at heart. Our Long Island family law attorneys are relentless in pursuing the best possible results for our clients whether it’s negotiating a settlement or battling it out in the courtroom. Call our law office at (516) 345-9900 or contact us online to schedule your free, no-strings-attached consultation today.

If you are looking at our website, you may be going through some very tough times. You may have major, immediate concerns and are ready to proceed, or perhaps are in an early phase of the decision-making process. We get it! Our team is here to help you un-complicate your life when you need it the most. We do more than represent; we explain and educate about the law and the options along the way. We work as a team with each client all of the time. There are no exceptions.

It is simply no secret that Family and Divorce Law are very personal and emotional subjects that can be difficult for families to navigate. After all, it often means major changes in the dynamics and finances of the home. It can even mean litigating against each other in court. This very truth is the reason why most attorneys elect not to practice any of these areas, but we embrace the challenges and handle them all. There are few, if any, other law firms on Long Island that exclusively handles what we handle and only what we handle.

Finding a law firm is easy. The real challenge is finding the right group of professionals who can provide representation that’s thorough, effective, and fair during the entire process. Often, a case is not simply determined by how bright or forceful the lawyer may be, but by how much respect they have within the courts and with other lawyers. Our firm has a retired Family Law Judge on staff. Our attorneys are in court to interact with those within the system on a daily basis. We regularly represent people who work within the Court system when they face their own personal legal issues. Again, these three areas are the only types of law that we practice, and we do it every single day. We represent every type of person imaginable from ultra-high net worth to those on a shoe-string budget, fathers and mothers, young and not so young, professionals and stay-at-home parents, and the list goes on. We handle simple cases that settle quickly, as well as cases that ranked as some of the longest litigated. If within our practice areas, we have done it successfully before and will do it successfully again for many years to come.

The Law Offices of Seidner & Associates, PC. understands the intimacy and complications associated with family matters. Our committed attorneys and staff will work to ensure your needs are met. Whether you are facing a divorce, a child custody dispute, or orders of protection, you need a law firm that truly cares and has a proven track record of success. We invite you to review our testimonials from actual former clients. Many came to our firm from other law firms and express the difference the change made in their lives. Most clients do start with us and then finish with us. All of our reviews are real, and we never engage in any of the practices that might artificially enhance our appearance to the public. The positive reviews on Google, Super Lawyers, Avvo, and, for example, were all submitted by former clients, and we hope that you will not only look at the rating but read the words.

Please contact us to experience our style of legal practice in the areas of Family and Divorce Law. We think you will see we really are different.

What Our Clients Say

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The Law Offices of Seidner & Associates, PC

Principal & Senior Attorney

Matthew Seidner-Esq

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After husband refused to voluntarily produce financial documents, the firm issued countless subpoenas and located hundreds of thousands of dollars of which half was awarded to our client but was previously unknown to exist.

Obtained physical custody for mother on the eve of trial by establishing that the father would lose in light of his history of domestic abuse and being absent from the child’s life and that if trial was to proceed, his potential financial misdeeds, including potential tax evasion, would be brought before the judge.

Obtained a modification of a prior custody order by achieving custody of teenage boy for our client, the father, and joint custody of the younger child. Also handled modification of the child support obligation in favor of our client.

After filing a Motion to Dismiss a Family Offense Petition brought against our client, the Petitioner withdrew the meritless petition rather than litigating a case where losing was inevitable thereby saving our client substantial counsel fees and aggravation.

Obtained permanent stay-away Order of Protection against a mother who was repeatedly indicated by CPS without a trial obviating the children’s need to testify against their mother yet securing all of the possible benefits for our client.

Successfully held father in contempt of court and then successfully argued that the court erred when it allowed the father to purge his jail sentence for a small fraction of his arrears. When the father did not pay, he was incarcerated. After incarceration, the father attempted to stay his sentence, but the Firm successfully defended

Settled contentious custody matter in favor of father with equal parenting time while, very significantly, avoiding trial sparing three children with special needs from having to endure court proceedings despite mother’s constant threats that she would do whatever was necessary to minimize the father.

The firm was able to successfully declare our client’s marriage to the Defendant null and void after we obtained irrefutable evidence that the Defendant was still married to his first spouse when he allegedly married our client.

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