The IPMO Logo incorporates the ancient Ogham alphabet. 

From Wikipedia;

"Ogham (/ˈɒɡəm/ OG-əm,[4] Modern Irish: [ˈoː(ə)mˠ]; Old Irish: ogam [ˈɔɣamˠ]) is an Early Medieval alphabet used primarily to write the early Irish language (in the "orthodox" inscriptions, 4th to 6th centuries CE), and later the Old Irish language (scholastic ogham, 6th to 9th centuries). There are roughly 400 surviving orthodox inscriptions on stone monuments throughout Ireland and western Britain, the bulk of which are in southern Munster"

In our logo, the letters IPMO, the initials of the organisation, are spelled out from bottom to top in the Ogham style. As our organisation is headquartered in the South East of Ireland, where many of Ireland's surviving ogham stones can be found, we are paying tribute to Ireland's ancient heritage. 

Theories of the origin of the Ogham alphabet have settled on a consensus that it was used for secret communication between Irish tribes, in opposition to the Romans and Romanised British that ruled Britain at the time [1]. It was, in a sense, a form of cipher. The use and understanding of a private alphabet was helpful for the indigenous Gaelic population in resisting a very real threat of invasion [2]. Experienced mediators know only too well the power of language to unite and also divide. 

The inscriptions in the Ogham language on monumental stones are written in what's known as Primitive Irish, a language in use from the 4th to the 8th centuries in Ireland and western Great Britain. 

A useful site to learn the ogham alphabet is Ogham.co

References

[1] Carney, J (1975) "The Invention of the Ogam Cipher", Ériu, Vol. 22, pp. 62–63

[2] Ryan, Catriona (2012). Border States in the Work of Tom Mac Intyre: A Paleo-Postmodern Perspective. Cambridge Scholars. ISBN 9781443836715. Retrieved 16 January 2019.