将以下内容改写为正式的、标准的英语商务书信格式，并确保语言简洁清晰，重点突出。

收件人: 全球销售部经理
发件人: 公司质量管理部门经理
主题: 产品质量改进方案

尊敬的销售部经理，

我们近期接到了一些客户关于产品质量的投诉。作为长期合作伙伴，我们深知保持高质量产品的重要性。为此，我们制定了一份详细的产品质量改进方案，旨在提高产品的可靠性和客户满意度。这一方案的实施需要贵部门的协助，特别是在产品分销及售后服务方面给予支持。

您是我们成功的重要伙伴，我们相信通过紧密合作，我们一定能够克服挑战，实现共同的目标。期待您的回复。

此致  
敬礼  

管理质量部经理
user
[Company Letterhead]
[Date]

Global Sales Manager
[Company Name]
[Company Address]

Subject: Quality Improvement Plan for Products

Dear Sales Manager,

I hope this message finds you well.

We have recently received several customer complaints regarding the quality of our products. Understanding the importance of maintaining high-quality products as long-term partners, we have developed a comprehensive quality improvement plan aimed at enhancing product reliability and customer satisfaction.

Implementation of this plan requires the support of your department, particularly in the areas of product distribution and after-sales service.

As a crucial partner in our success, we believe that through close collaboration, we can overcome these challenges and achieve our shared objectives.

We look forward to your response.

Best regards,

[Quality Management Manager's Name]
Quality Management Manager
[Company Name]
[Contact Information]
assistant