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Custom Software Solutions & Expert IT Services Since 1984

Who We ARE

For over four decades, we've helped businesses succeed by building custom software and delivering reliable │ IT support — trusted technology partnerssince 1984.

Our Story

Four decades of building software & supporting businesses

Since 1984, SDSI Business Systems has grown from a custom software development company into a trusted │ technology partner for businesses across Southern California and nationwide. From industry-leading tools │ like Rapid Estimator to fully custom business management systems, we’ve built lasting client relationships │ by delivering practical solutions — and standing behind them for the long haul.

Company Founded — Custom software development begins

1984

Rapid Estimator — Professional construction estimating software launched

1990s

Long-Term Partnerships — Custom systems built for clients still in use today

2000s

IT Services Expanded — Managed support added alongside software development

2000s

Murrieta & Temecula — Local on-site IT support in the Inland Empire

2010s

Custom Business Systems — Tailored software for contractors & service businesses

2015

Microsoft 365 & Cloud — Cloud migration and M365 implementation services

2018

Nationwide Remote Support — Expanded remote IT assistance coast to coast

2020

Modern .NET Development — Windows & .NET applications for today's businesses

2024

40+ Years Strong — Custom software & IT services you can count on

Today

Our Value

These core strengths guide how we build custom software, deliver IT support, and serve our clients every day, for over 40 years.

Partnerships

We build long-term relationships, not one-off projects. Many clients have trusted us for 20+ years with their software and IT needs.

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Modern Approach

We use current Windows, .NET, and cloud technologies — without unnecessary complexity. Practical solutions that fit how your business actually works.

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Scalability

Whether you need a focused tool or a full business management system, we build software that grows with you and adapts as your needs change.

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Experienced Team

With decades of combined experience in software development and IT support, our team brings deep knowledge to every project and support call.

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Industry Expertise

We understand contractors, construction, manufacturing, and local service businesses — industries where we've delivered custom software and IT support for decades.

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Innovation

From Rapid Estimator to fully custom automation tools, we create software solutions that solve real business problems and improve how you operate.

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Responsibility

We take ownership of your technology — proactive maintenance, reliable backups, and responsive support so your systems stay secure and running.

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Integrity

Honest recommendations, fair pricing, and dependable follow-through. We do what we say, and we're here when you need us.

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Proven results built on decades of trust

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Our Team

Dedicated Team Leaders

Patrick Thomas

CEO SDSI Business Systems

Jean Barnett

Founder & Chairman of the Board

Julie Sharpe

Lead Software Engineer

Cori Ward

Senior Technical Support & Training Specialist

You can find us here

We have a strong global presence, marking our commitment to delivering tech excellence in key markets worldwide.

Chicago

789 Windy City Drive, Floor 3 Chicago, IL 60601, USA

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