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There are many methods by which the state of dispersion of pigments may be studied, either in the liquid paint or in the dried film. They range from essentially practical methods useful for production control to sophisticated laboratory techniques capable of providing quantitative data on the number, size, and type of particles present in a dispersion.

This series of articles is based on the new 64pp booklet prepared by the author, aided by many of his colleagues in Tioxide International Ltd, and published last month under the title “Dispersion of Tioxide Pigments in Non‐Aqueous Media”. The book describes the principles of dispersion and gives practical advice to help coatings chemists disperse Tioxide pigments in the most efficient and economical manner possible. Section A defines dispersion and gives a brief explanation of mechanisms that may be concerned in the production of a stable dispersed system. It presents an outline scheme for the formulation of millbases that can be applied to all combinations of titanium dioxide pigments and resins. The effects of resins, solvents, and “dispersing aids” are also considered. Section B describes the types of paintmaking machine used in the industry today. The sections of the original book to be ommitted from the series of articles to be published in the journal are those that it is considered have already been adequately covered in the literature.

The flowpoint titration, as it has evolved over the years, is a natural development of the older oil absorption test. Instead of titrating the pigment with refined linseed oil, it is titrated with resin solutions of different concentration. For each pigment‐resin‐solvent system, the relationship between resin concentration and the volume of resin solution needed to form a free‐flowing paste is graphed.

Generally the physical properties of the vehicle have a greater influence on the physical nature of a dispersion than those of the pigment, and in practice the choice of binder solids and thinning solvent are important.

A well appreciated difficulty in paint formulation is the scaling‐up of laboratory data, and to obtain optimum performance on a commercial scale adjustments in p.v.c. (f) and in resin solids concentration have to be made. In the laboratory the millable p.v.c. (f) of a given formulation may be above, or more usually below, the value indicated by the flowpoint data, and depends mainly on the ability of the particular milling machine to cope with the quantity and nature of the millbase. In large‐scale manufacture using high‐speed shear impellers, a somewhat higher value than the experimentally determined p.v.c. (f) can be used, but for a ballmill it will be only slightly higher than the value millable in the laboratory. The concentration of resin solids has also to be adjusted, and here it is important to ensure that it is high enough to prevent pigment reagglomeration on let‐down.

Since the size of surface defect which has a detrimental affect on specular gloss is comparable with that of some pigment particles it follows that in paint systems where pigment is present at the surface, gloss may be significantly affected. The size of titanium dioxide crystals, for example, is about 0.2 ?m so depending on the paint system used, the type of pigment and its concentration are important factors.

Views about the nature and purpose of evaluation have developed quite dramatically over the last two decades. Unfortunately many peoples' expectations about what evaluation should be doing have not kept pace with these developments. In addition there has been a large amount of work carried out on the evaluation of general educational and social programmes, and much of this is both parallel to, and complimentary to, the evaluation of management training. This paper reviews recent trends in both fields using ideas from educational evaluation to clarify some of the problems encountered repeatedly in training evaluation and to suggest what might be more realistic expectations of evaluative activities.

Within both Western and Eastern traditions of virtue ethics, there is a Doctrine of the Mean, suggesting that errors may lie either in excess or in deficiency. The need to avoid both excess and deficiency in the allocation of finite resources is a concern in many sorts of business decisions, some with ethical implications. One finite resource is the resource of attention, and ethical problems can arise from failures to attend to important things. Both Aristotle and classical Confucianism accept the importance of paying attention to circumstances rather than following fixed rules or blindly maximising value. For organisations to give appropriate attention to different things requires suitable intra-organisational reporting and communication. Then there is still need for awareness that resources are finite, and for activity that is sustainable, highlighting the related idea of harmony, especially salient in the Confucian tradition.

The first three articles have been concerned with the substance, the conceptual context and the skills of negotiating. This final section is devoted to the ways and means of learning how to negotiate. Some relevant ideas on learning are discussed and a number of resources are listed to help those who are designing programmes in this area.