Douglas J.A., speaking for the majority, stated that “the legal source of the labour arbitrator is not limited to the explicit provisions of the treaty, since the industrial common law – industry and company practices – is part of the collective agreement, although it is not expressed in it.” Compared to the real experience of the management union in contract management, this diktat seems too broad. It may be premature, as no “grounds for appeal arbitration” have yet been developed consistently. To obtain such a justification, much more work is needed to identify and analyze the standards that are used to shape arbitration notices. The purpose of this paper is to examine in detail one of the most important standards on which so many of our decisions are based. Customs and practice profoundly influence every area of human action. The Protocol governs relations between States; etiquette influences an individual`s social behaviour; Habit determines most of our daily actions; and Moreen help determine our laws. It is therefore hardly surprising that current practice in an industrial enterprise plays an important role in the management of the collective agreement. • It must be known to both management and the union. While there is no need to “negotiate” a past practice, both parties need to be aware. On the management side, it is sometimes not good enough for a low-level foreman to know that it has to be superior management. • It must exist for a relatively long time.

The more a practice is in force, the more weight it carries. We are talking about years, not weeks or months. Many arbitrators think that a practice must last 3-5 years and be “cross-over-contracts”, that is, it must have been in practice for the duration of at least 2 contracts…