Thereza Macnamara attained her first degree in applied physics and her master's degree in microwaves at London University.
After two years of teaching physics up to Advanced level, she worked as a microwave engineer at G&E Bradley. She then worked as a research physicist for Morganite Research and Development before returning to work as a microwave engineer, working on a standard field facility, waveguide components, thermistor detectors, and calibration at Wayne-Kerr Laboratories, Flann Microwave Instruments and Bradley Electronics. After a short break to have a family, she returned to work as an examiner at the British Patent Office and lecturing in mathematics and physics whilst her children were growing up. She then took up a post as a senior RF engineer at ERA Technology, where she worked on antennas, feed networks and as an EMC engineer, before taking up the post of an electromagnetic specialist at BAE Systems where she worked for 17 years. Whilst at BAE Systems she worked in the R&D department and on Nimrod, Typhoon, Harrier, Tornado and Jaguar aircraft, and then became the technical coordinator of the EU funded research project IPAS (Installed Performance of Antennas on AeroStructures). Apart from many technical papers, she has also authored many reports, including a Code of practice for the petroleum industry.
She has tried to raise the profile of women in engineering and acted as a school Ambassador.
She also is a silversmith with her own maker's mark, makes chairs and high stools, restores antique furntiure, plays the piano, is a stone carver and does portrait drawing.
Other activities include being the treasurer for two charities and associations and supporting 13 other charities. She is now retired but when she was working full-time at BAE Systems she ran two tuckshops making about £3000 per year for charity. During an eighteen month period the Farnborough site (of about 1000 staff) raised £80,000 for charity, over £10,500 being raised by her alone. Sight Savers named her as one of their 14 individual donors in their 2006 brochure and invited her to a recepetion where she met Joanna Lumley and Denis Lawson.