For a good many years past I have been allowed to comment, in letters to _The Times_, upon points of International Law, as they have been raised by the events of the day.

These letters have been fortunate enough to attract some attention, both at home and abroad, and requests have frequently reached me that they should be rendered more easily accessible than they can be in the files of the newspaper in which they originally appeared.
I have, accordingly, thought that it might be worth while to select, from a greater number, such of my letters as bear upon those questions of War and Neutrality of which so much has been heard in recent years, and to group them for republication, with some elucidatory matter (more especially with reference to changes introduced by the Geneva Convention of 1906, The Hague Conventions of 1907, and the Declaration of London of the present year) under the topics to which they respectively relate.
The present volume has been put together in accordance with this plan; and my best thanks are due to the proprietors of The Times for permitting the reissue of the letters in a collected form.
Cross-references and a full Index will, I hope, to some extent remove the difficulties which might otherwise be caused by the fragmentary character, and the chances of repetition, inseparable from such a work.
T.E.H.
EGGISHORN, SWITZERLAND, _September_ 14, 1909.
* * * * * PREFACE TO THE SECOND EDITION I have again to thank _The Times_ for permission to print in this new edition letters which have appeared in its columns during the past four years.

They will be found to deal largely with still unsettled questions suggested by the work of the Second Peace Conference, by the Declaration of London, and by the, unfortunately conceived, Naval Prize Bill of 1911.
I have no reason to complain of the reception which has so far been accorded to the views which I have thought it my duty to put forward.
T.E.H.
OXFORD, _January_ 10, 1914.
* * * * * PREFACE TO THE THIRD EDITION This, doubtless final, edition of my letters upon War and Neutrality contains, by renewed kind permission of _The Times_, the whole series of such letters, covering a period of no less than forty years.

To the letters which have already appeared in former editions, I have now added those contained in the "Supplement" of 1916 (for some time out of print) to my second edition; as also others of still more recent date.

All these have been grouped, as were their predecessors, under the various topics which they were intended to illustrate.