Dale Warner practiced immigration law from February 1979 in San Jose and San Francisco until April 2004. He specialized in employment-based visa applications of a temporary and a permanent nature. He was graduated from Michigan State University in 1962 and The University of Michigan Law School in 1965. He was admitted to the bar of the Supreme Court of the United States in 1983. He contributed about 10% of his time to the community through various pro bono programs.

The July-August 1999 issue of San Jose Magazine announced the results of a surprise local poll it took among lawyers, and Dale Warner was listed among the eight "best" local immigration lawyers, or one of "the eagles others in their flock allege they would flock to, if they needed some legal advice."

The July 2001, May 2002, and July 2003 issues of San Jose Magazine also reported polls of attorneys, and Dale Warner won recognition in each poll as one of the top 300 attorneys in Silicon Valley and one of the top six in the field of immigration law.