The short answer is that you cannot do so, especially in a larger organisations, because of the diversity in staff status and positions, and the variety in functions, roles and expectations. However, if one addresses the various strands of this question, there might be possibilities.
First of all, to make anything 'meaningful' to someone it has to have RELEVANCE to them: either personal, professional or developmental. Wherever training has relevance to either the present or future in one of those key areas, the training will be more sought after and valued. Hence training will either have to focus on the personal aspect (emphasising desired attributes like how to be successful, an achiever, more assertive, more competent or whatever), the professional aspect (relating to improving one's job functions) and the developmental aspect (which focuses on promotion, personal enhancement and advancement, changing career etc). In short, on anything that leads to better understanding of the self, one's job or one's future.
For those reasons any one course, seminar or workshop cannot be applied, or even adapted, across the board. It would be like giving the same reading book to different ages of children without taking into account their age, ability or maturity. There would be lots of resentment and disappointment because it would suit some and not others, thus disappointing the expectations and ultimately defeating the objectives.
Training has to be specific and tailor-made to be really worthwhile and useful. One size definitely won't fit all. Even training that can be applied on the general personal level: like how to boost confidence, improve communication or interview skills, for example, still has to be customised according to the level of the staff being trained because the needs of new recruits in those areas would be quite different from those of senior managers.
So to answer your question, the training must be relevant for each person but, to make it adaptable is trickier because its content will really depend on the specific needs the training is addressing and the groups of employees who will be benefiting.