The only condition is that it works via a proxy, i.e.
My only condition is that she must always be on public display.
His only condition being, that they were new ones.
His only condition was that his paintings be housed in a suitable venue.
Sa seule condition était que les tableaux soient exposés dans un lieu adapté.
The willingness to collaborate is the only condition for success in this city.
La volonté de collaborer est dans cette ville la seule condition pour réussir.
It seems to be the only condition among all the genius.
Il semble que c'est la seule condition commune à tous les génies.
The patient must fulfill the only condition - to practice regularly.
Le patient doit remplir la seule condition - pratiquer régulièrement.
Good quality is the only condition for our eternal development.
Une bonne qualité est la seule condition pour notre développement éternel.
That's the only condition under which it would get sent back.
C'est la seule condition en vertu de laquelle elle serait renvoyée.
To let him is the only condition required.
Le laisser faire, c'est la seule condition requise.
That was the only condition when we got married.
C'était la seule condition quand nous nous sommes mariés.
Seriously, this is the only condition of the pursuit of happiness.
Le sérieux, c'est la seule condition de la quête du bonheur.
Of course, that is not the only condition.
Ce n'est naturellement pas là la seule condition.