A "plan" is a description of what is to be done. "Planning" is the act of devising a plan. A "strategy" is much more than that. Whereas a plan is deterministic, a strategy is thought through more deeply and takes account many possibile events, which may be unknowable, and plots a course of action that is adaptive, thoughtful, and reacts as needed. For example, a military commander needs to have a strategy, not just a plan.

"Planning" is the noun in both sentences. "Sensible Planning"

I think their definitions overlap somewhat, but planning feels more general while stragey (or strategizing) feels more technical. Here are some example I hope help show the overlaping meaning and difference in meaning: - Financial planning is important to a good business. - Careful planning made the party a success. - Planning ahead will prevent a lot of difficulties later on. - He is a specialist in military strategy. - The government is developing innovative strategies to help people without insurance get medical care. - They are proposing a new strategy for treating the disease with a combination of medications.

I think the distinction between these concepts is even confusing for most native speakers. For me, strategic planning is the entire process of developing high level objectives and putting in place more detailed plans designed to achieve those objectives. The development of those plans could be referred to as "planning". There are of course many types of planning and development of plans that would not be considered strategic planning. For example, planning for a vacation or for what you eat for dinner this week generally wouldn't be referred to as strategic planning.