1. A strictly hierarchical top-down structure: The “you should not share knowledge outside your department without your manager’s approval” syndrome.
2. Focus on short-term objectives: the “no need to share knowledge since once objectives are met, it wont be needed anymore” syndrome.
3. Reward achievements of each individual based solely on personal objectives: the “you are judged on what you achieved, not on what others have achieved with your help” syndrome.
4. Organizational silos that do not (or poorly) communicate/collaborate: the “we cannot possibly need help from anyone outside our very experienced and specialized group” syndrome.
5. Lack of trust: the “why should I take the risk to help whom I compete with, I wouldn’t get the recognition for it anyway” syndrome.
6. Internal politics: “Knowledge is Power so I retain it” syndrome.
7. Lack of Awareness of internal knowledge: The “I do not expect anyone in the company to have the experience/skills I need” syndrome.
8. Lack of Availability of internal knowledge: The “others probably could benefit from my experience but I’m too busy to check, let alone actually help” syndrome.
9. Too much Pride: The now too famous "not invented here" syndrome.
10. The confidentiality issue: The “we fear that some vital competitive knowledge can get into the wrong hands, so the least we share it, the smaller the risk” syndrome.
11. Job Description framing: The 'No-one's paying us to have a wider vision' syndrome.
12. Groupthink effect: The 'We'll define our stakeholders as the people we already know' syndrome.
13. Only money talks: The 'those so-called stakeholders aren't actually funding anything directly, so they're not real customers' syndrome.
14. Perfectionism resulting from fear of being wrong: the "I won't share until I'm certain it's perfect" syndrome.
15. Modesty resulting from lack of encouragement: the "who am I to teach others, of course they know" syndrome.
16. Top-executives misunderstanding KM challenges: The "this knowledge sharing sounds great! Can you order everyone to do it tomorrow please?" syndrome!!!
You can test your organization against these 16 cultural traits. The more of them fits your workplace, the more of a challenge you will have to promote knowledge sharing. Some are more difficult to deal with such as internal politics, but I would conjecture that you will need to address all the relevant traits at some point in the process. They all have their importance and only one of them - deep rooted in the organizational culture - can jeopardize leveraging knowledge efforts.
I have recently (Feb. 08) added 4 more traits, check this post.