• Trained and qualified as an auditor with Deloitte & Touche between 1983 and 1989.
• Worked as a Chief Accountant at Alico Kenya Ltd (now Liberty Life) from 1989 to 1993.
• Worked as a Finance Manager & Company Secretary at British-American Insurance Company (K) Limited from 1993 to 1996.
• Worked as General Manager & Company Secretary at British-American Insurance Company (K) Limited from 1997 to 2002
• Worked as a Finance Director at ZEP-RE (PTA Reinsurance Company) from 2002 to March 2005.
• From April 2005, Jackson Maingi has been a full-time Consultant and the Managing Partner of Maingi Jackson & Associates.

Apart from the relevant experience acquired from the employment environment, Dr. Jackson Maingi has a lot of consultancy experience including the following:

• He has and continues to be the team leader in a large number of external and internal audit clients. Some of the notable internal audit clients where Jackson has been a team leader include Zep-Re (PTA Reinsurance Company), Mayfair Insurance Company and New Apostolic Church, Corporate Insurance Company Limited and many Pension Schemes.
• He has and continues to be the team leader in a large number of Strategic Planning consultancies. The ones done so far this year include the following:
  - Central Bank of Kenya (CBK) Pension Fund.
  - INVESCO Assurance Company Limited.
  - Organization of Eastern and Southern Africa Insurers (OESAI).
  - OESAI Non-Life Pool.
  - Hazina Investments Company Limited Jackson is also one of the big trainers in the area of Strategic Management.
  
• He has participated in a World Bank funded Consultancy on the privatization of National Insurance Company of Tanzania (NICT) Limited. This was between May 2005 and September 2005 and the assignment was carried out in Dar-es-Salaam.
• He has and continues to be a leading trainer Corporate Governance and Risk Management areas.
• He has participated in several Human Resource Consultancies geared towards Remuneration and Performance Management. What is involved here is staff grading emanating from Job evaluations, designing performance appraisals, and aligning staff pay to the various grades. Jackson Maingi is quite familiar with the Hay Job Evaluation system and has used it several times.

Some of the organizations where Jackson carried out Human Resource consultancies include Bamburi Cement Limited, Bamburi Special Products Limited, James Finlay East Africa Limited, Hellar Park Limited in Mombasa, Neddloyd Shipping Lines Ltd etc.