Soteri, who also worked at the Travel Protection Group and Abta during her long career in the industry, died suddenly this week, aged just 52.
She had been on long-term sick leave from her commercial director role at ITT.
ITT board member Sue Kavanagh said she had been deeply shocked to hear the news.
She said: “Ande had a bubbly and effervescent personality and a great knack of making everyone feel at ease.
“At ITT functions I often saw her welcoming new members into the fold and quickly making them feel part of the group.
“I will always smile when I think of Ande and miss the great laughs and fun we had together over the years.”
ITT chairman, Steven Freudmann, added: “I worked with Ande for almost 30 years at Abta and ITT.
“I am deeply shocked at losing her at such a young age.
“Ande worked for ITT for the last 11 years and was a wonderfully loyal and enthusiastic supporter of the
institute, despite being plagued by ill health for the past few years.
“She will be sorely missed both professionally and personally.”