Step 1: Recall orbital overlap condition.
Effective overlap occurs when orbitals are aligned along the internuclear axis (the line joining two nuclei).
Step 2: Application to s and p orbitals.
- The spherical s-orbital can overlap with a p-orbital lobe only if the lobe points along the axis joining the nuclei.
- If perpendicular, acute, or obtuse angle → poor or zero overlap.
Final Answer:
\[
\boxed{\text{pointing along the axis joining the nuclei}}
\]