The firm was founded by Fred H. Hennighausen and A.J. Olsen in 1985.  The firm is engaged in a general civil and criminal practice, providing quality legal services in a professional timely manner, at a fair fee. The attorneys of the firm pursue areas of practice including water law, real estate, corporate and commercial matters, estate planning and probate, administrative, white collar crime, trial and appellate practice, collections and creditors' rights,family law, and alternative dispute resolution.

The attorneys of Hennighausen & Olsen have been and are leaders in the legal community and the community at large. The firm is committed to community service, and all of its members are active with local agencies, charities, churches, and in pro bono legal representation. Further, the firm is committed to staying abreast of the changing legal environment confronting its clients and making available to its clients practical and cost-effective representation.