The leader is the single most important variable in the nymph fisherman’s set-up, and is often the key factor in determining success or failure. The French leader performs in a different way to the conventional leader, thus setting French leader technique apart from other methods. An enormous amount has been written in the quest for a perfect action, and as a result French leaders have evolved to take many different forms. In this chapter, we shall look at some of the main leader variants for both sight and indicator nymphing and try to identify what are currently the most useful approaches.

French leaders differ from conventional leaders not only in terms of their greater length, but also their construction, with most top French flyfishermen opting for knotted leaders comprising multiple strands of nylon of varying length and diameter. To many British flyfishermen, perhaps used to buying ready-made leaders ‘off the shelf’, leader constructions of this type can seem at first sight rather complex and technical.

It is certainly true that some time and effort is required to build a couple of knotted leaders that will be appropriate for most purposes. However, this is an investment that will be richly rewarded. These leaders offer major advantages both with regard to delaying the onset of drag and optimising presentation of the fly, allowing for the delicate delivery of even very long tippets. Furthermore, once these leaders are put together they should last a whole season, with only changes to the tippet being necessary.

For ease of comparison for British and American readers, the table shows metric and imperial diameters side by side. Breaking strains (BS) are approximate.

Piam’s original French leader

Piam, an exceptional sight fisherman from the Jura, is widely credited with the invention of the modern French leader in the mid-1980s. Piam’s revolutionary approach consisted of developing a leader of more than 7 metres in length, at a time when most fishermen were using leaders of 3 to 4 metres. The other distinctive feature of Piam’s leader was that it was constructed from 8 strands of nylon, with each strand progressively lengthening as the diameter of the nylon decreased. The effect of this construction was to impart a ‘slow’ action to the leader, meaning that the leader does not immediately extend over the water. This action permits a delicacy of presentation that is crucial when approaching very shy fish in clear water. Piam’s approach also provides substantial advantages in allowing the angler to fish very fine diameter tippets at significant distance.

Piam’s sight-nymphing leader

Piam pioneered the use of a very long tippet of between 2.5 and 2.8 metres in length, an approach that has now been widely adopted in France for both sight nymphing and for dry fly fishing on large rivers. The reasons for this are not hard to find: long tippets improve presentation, allow more time for the nymph to sink, and promote longer drag-free drifts.

Philippe Boisson’s French leader

As we have seen, Philippe Boisson was an early disciple of Piam who, together with Norbert Morillas, took sight fishing a nymph to new levels in the 1990s. Boisson’s influence on the development of flyfishing in France has been significant, both as a fisherman and as a writer. He was for many years editor of the outstanding French fishing magazine Pêches sportives, and his book De la pêche à la nymphe (2010) is one of the most thoughtful flyfishing books published in any language.

Although Boisson successfully used Piam’s leader construction for many years, he was troubled by its limitations when fishing a tippet of 0.12mm or larger. As the last section of Piam’s leader was itself 0.12mm, it was not possible to add a tippet of 0.12mm or 0.14mm without compromising the performance of the leader. The angler either needs to dispense with the last section of Piam’s formula, thus shortening the whole leader, or he is obliged to modify Piam’s construction. The former is undesirable in most situations, and the latter is cumbersome to achieve on the riverbank.

Boisson’s solution to this problem was to propose an alternative, much simpler, leader construction. Boisson’s leader uses 5 strands of nylon, each of equal length, starting at 0.40mm at the butt and decreasing to 0.18mm for the section preceding the tippet.

Philippe Boisson’s leader

As the strands are of equal length, the action of Boisson’s leader is neither ‘slow’ nor ‘rapid’. However, the function of the final 0.18mm strand is to create a break as the leader unfurls, thus causing the tippet to land gently and loosely on the water. In order to overcome the challenge of connecting the 0.18mm strand of the leader to a much finer tippet, Boisson recommends an adapted version of the surgeon’s knot. To make a secure connection, his adaptation involves doubling back the end of the tippet, and then making not less than five turns within the loop of the knot.

Boisson’s leader has several advantages and is very versatile. It does not need to be changed whatever the diameter of the tippet, and his construction has fewer knots travelling through the rings of the rod and on the surface of the water. This leader can be used on different types of river and is suitable for both sight nymphing and dry fly fishing. On smaller rivers, the leader can be shortened by decreasing the strand length to about 60cm each, and by reducing the length of the tippet to 1.5 metres. A shorter version of Boisson’s leader is also a good starting-point for fishermen trying this technique for the first time.

Indicator Nymphing Leaders

Indicator nymphing with a French leader has developed to take several different forms. However, the principal distinction to be made is between long-distance nymphing using an indicator which is designed to float, and short-range tactics where the indicator does not float and the rod is held high in order to keep both line and leader from lying on the surface of the water.

Boisson’s short-range ‘rod-high’ indicator leader

When combined with an indicator, Boisson’s equal-length strand formula also works very well for short-range, rod-high, indicator nymph fishing. The main differences are that the first strand is 0.45mm diameter, while the final strand is 0.20mm diameter and incorporates two equal lengths of nylon of different and contrasting colour, which serve as an indicator. The tippet should be of the same length as, and certainly not less than, the depth of the water being fished.

Although the length of the strands can be modified, the leader needs to be relatively long. If not, the fly line will tend to rise up the rings of the rod. As the rod is held high when using this technique, this will lead to gravity acting on the line, pulling line and leader back through the rings of the rod.

Long-range indicator nymphing, in which both line and leader lie on the surface of the water, is a popular technique with many French competition fishermen. The last strand of the leader consists of one or more lengths of 0.20mm coloured nylon which end with a perfection loop of between 3mm and 5mm, to which is attached the tippet. The coloured nylon strands and perfection loop are covered in white Mucilin or grease in order to make them float, thus making a very efficient bite indicator. Again the length of the tippet must at least match, if not slightly exceed, the depth of water being fished.

Although it is perfectly possible to use a leader comprising strands of equal length for long-range indicator nymphing, many fishermen prefer a leader with a slightly slower action. This is achieved by graduating the length of the strands comprising the upper part of the leader.

‘Slow’ action long-range indicator leader

Nylon Types

There are many different materials that can be used for French leaders. Indeed, most French flyfishing shops sell an array of nylon types and diameters that would be quite bewildering to most British and American anglers.

The original and still most popular French leader material for strand diameters between 0.50mm and 0.25mm is Maxima, which has very little memory and a good level of stiffness. Another very good alternative is Kamoufil, which comes in a camouflage colour and is also sufficiently stiff to turn over a long tippet.

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