вести себя, как подобает, быть ответственным
вести себя надлежащим образом, относиться к делам ответственно;
?

контекст
Each member shall:
(c) be just and faithful to the LLP and to the other members in all transactions relating to the business and affairs of the LLP
(d) conduct himself in a proper and responsible manner
(e) use his best endeavours to promote the business of the LLP

(LLP Agreement, UK, 2010)