Here is a professional and corporate color palette for a business consultancy website:

1. Navy Blue - 
                            
                            #001F3F
                         - Symbolizes trust, professionalism, and stability
2. Slate Gray - 
                            
                            #6C757D
                         - Represents sophistication and intelligence
3. Steel Blue - 
                            
                            #4682B4
                         - Evokes professionalism and dependability
4. Olive Green - 
                            
                            #556B2F
                         - Signifies growth, harmony, and stability
5. Silver - 
                            
                            #C0C0C0
                         - Reflects modernity and elegance