The Waterman Expert was made in three versions, now referred to as Mk.l., Mk.ll., and Mk.lll..
The Expert I was made from c.1988 to 1999:
It is characterised by, the two toned, 'slab sided' nib and has a stlysed 'W' between two gold filled cap rings.
The Expert II, made from 2000 to 2013, has a more conventional nib, a metal plate on the end of the cap stud, and the words 'Waterman. Paris' between the cap rings:
The Expert III, made from 2014 to the present, has one wide and one narrow cap ring:
The Expert was one of the first 'non tubular' French Waterman models, I use the term loosely to describe a pen that is essentially made from two, usually brass, tubes forming the barrel and cap. In 1999 Waterman offered 13 models, only 3 were not of tubular design: the Expert, Edson, and Hemisphere.
In 2000 the catalogue featured 11 pens, in addition to the 3 mentioned above the Carene and the Phileas were added, making 5 from 11 non tubular pens.
Jumping forward to 2005,the catalogue contained 18 models, including the Serenite(bent), Edson, Exception(square), Carene (boat shaped), Charleston, Expert, Ici et La, Audace, Hemisphere, Phileas, and L'Etalon. 11 out of 18.
Over the next twenty years the fountain pen market changed considerably as public taste shifted. Many of the 'outrageous' designs fell by the wayside and, in the 2025 catalogue we find only five pens: Hemisphere, Allure, Exception, Carene and Expert. The Expert not only survived but thrived and Waterman now seem to be banking on it as the main money earner. From the current catalogue you can select from about 20 different Expert designs, the same pen in different 'clothing'.