Human-AI collaboration, widely known as hybrid or symbiotic AI, denotes a nuanced interaction between humans and artificial intelligence (AI) systems where both complement each other to achieve common goals. This approach doesn't merely involve performing tasks independently but rather involves collaboratively working towards optimizing output. The integration of human intuition and AI’s processing capabilities can lead to more robust, creative, and efficient solutions.

The primary features that characterize human-AI collaboration include the following:

• Shared Control: In human-AI collaboration, control is not solely vested in the human or AI. Instead, tasks are executed in tandem, playing on the strengths of both parties.
• Mutual Communication: Communication is bidirectional in this collaboration. Both the AI and the human contribute ideas, suggestions, and feedback.
• Continual Learning: The AI system learns from human input continually, which leads to increased efficiency and effectiveness over time.
• Adaptive: The collaborative system adaptively changes based on the tasks at hand and the responses from the human users.
• Complementary strengths: It combines human intuition and creativity with AI's statistical and analytical prowess, providing comprehensive solutions.

Implementing collaborative AI necessitates careful planning, understanding organizational requirements, and selecting the most suitable AI technology. The following steps can ensure a successful implementation:

• Needs Analysis: Carrying out a detailed analysis of the organization’s needs is a crucial first step. It helps identify areas where AI can play a vital role.
• Solution Evaluation: The next step would be to identify and evaluate potential AI solutions that align with these needs.
• Vendor Evaluation: It's important to assess vendors not just on their technology but also their ability to provide robust support in implementation and ensuring ongoing reliability.
• Workforce Training: For successful implementation, workforce training should be a priority. It ensures that the workforce is comfortable using the new AI systems and utilizing them to their full potential.
• Process Integration: AI should not be looked at in isolation. It needs to fit seamlessly within the current process landscape of the organization, leading to the need for its integration with existing systems.

The coexistence of humans and AI at the workplace brings an array of benefits:

• Expanded Potential: Harnessing AI capabilities while leveraging human skills results in broader problem-solving scope, faster decision-making, and enhanced creativity.
• Productivity Increase: AI can automate mundane workplace tasks, which helps save time and boosts overall productivity.
• Continual Learning and Improvement: AI continuously learns from interactions with humans, gradually enhancing its understanding of tasks and improving its responses.
• Inclusive Design: Human-AI collaboration offers opportunities to design inclusive work environments by considering diverse human perspectives.
• Mitigating Human Limitations: AI can effectively handle repetitive tasks, thus reducing human error and improving the quality of output.

While the benefits are compelling, integrating AI into human workflows isn't without its challenges:

• Ethical and Privacy Concerns: The reliance on AI raises significant concerns about data privacy and ethical implications around AI decision-making.
• Lack of Understanding: Misconceptions about AI's capabilities may lead to unrealistic expectations or fear of replacement, causing resistance among people.
• Skills Gap: There is a need for upskilling and retraining workforce to effectively collaborate with AI, which could be time-consuming and costly.
• Integration with Existing Systems: Achieving seamless integration with current systems can be a daunting task given the inherent complexities of AI.
• Autonomy vs. Control: Finding the right balance between delegation to AI and human control could be challenging.

The success of human-AI collaboration lies not in simply acquiring AI technology, but in its effective integration with the current workflow and the active participation of the workforce in this collaborative effort. A holistic approach towards human and AI interaction helps in delivering solutions that not only augment human efforts but also enrich human experiences and pave the way for a sustainable future of work.