The following are membership grades with post-nominals :
Affiliate: (no post-nominal) The grade for students, apprentices and those interested in or involved in mechanical engineering who do not meet the requirements for the following grades.
AMIMechE: Associate Member of the Institution of Mechanical Engineers: this is the grade for graduates (of acceptable degrees or equivalents in engineering, mathematics or science)
MIMechE: Member of the Institution of Mechanical Engineers. For those who meet the educational and professional requirements for registration as a Chartered Engineer (CEng) or Incorporated Engineer (IEng) or Engineering Technician in Mechanical Engineering .
FIMechE: Fellow of the Institution of Mechanical Engineers. This is the highest class of elected membership, and is awarded to individuals who have demonstrated exceptional commitment to and innovation in mechanical engineering.