About us

Serving the legal needs of businesses, people, and families since 2002

Why choose us

Because we do not look for occasional clients, we build relationships

Through personal, practical and cost-effective advice, we build long-term relationships with our clients, based upon understanding and care for your interests and needs. It comes to no surprise then that may of our clients have trusted your business and families for decades.

Because we make law plain and simple

We want you to understand your problem and get straight answers. You are not to be at a loss with legalese or a process you do not understand but only fear.

Because we make easy to hire a lawyer

Either you want one-off advice, work with us on a project basis, hire our day-to-day advice, or commit us with solving a concrete issue, we will be happy to find the best working relationship with you, customized to your real needs. Fixed fees, time billed or contingency fees are some of the fee arrangements we may put in place.

Because we care

Should you have not made up your mind yet, and wish an initial no-obligation meeting or conversation to know more about how we can help your business, your family or yourself, please, let us know.


In its current shape, Castro Sammartino & Pierini was founded in 2002. However, by various ways and under different names, some of its members had been practicing law for many decades already.

Hugo Alberto Pierini† began his professional career more than fifty years ago and was soon followed by many lawyers, including Pedro Roich and his son – and founding partner of Castro Sammartino & Pierini – Guillermo Hugo Pierini. These and other attorneys merged with the law practice of Mario Eduardo Castro Sammartino to found Castro Sammartino & Pierini in 2002.

Our people

Five lawyers work in the firm and we also have independent fee earners who join us to attend to projects, clients or specific needs, optimizing services and maintaining the highest cost efficiency for our clients.

Mario E. Castro Sammartino

Lawyer graduated with honors from the University of Buenos Aires.

Lawyer specialized in Corporate Counseling from the Pontificia Universidad Católica Argentina.

Commercial Arbitrator of the Arbitration Panel of the Public Bar Association of the Federal Capital

Guillermo H. Pierini

Lawyer from the University of Buenos Aires

Contact us

It will be a pleasure to meet you personally at our offices, or to take your call.

Tte. Gral. Juan Domingo Perón 679, 3rd. floor
C1038AAM - Buenos Aires


Follow us

Send us an email

5 + 6 =