Moving sales channels into the Global workspace and making default channels private would:

Create confusion and friction in adoption.

Reduce transparency and cross-functional collaboration.

Slack documentation highlights:

"Workspaces should be structured to align naturally with how teams operate. Making core channels private may limit discoverability and collaboration, which contradicts Slack’s goals for connection and transparency."

Options B, C, and D promote transparency and collaboration, which is the intended use of Slack across cross-functional teams.

(Reference: Slack Administration Study Guide - Change Management and Slack Adoption Strategies)

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The best practice in Slack for securely collaborating with external partners is:

"Use Single-Channel Guests for external users when collaboration is limited to specific channels. Admins should control guest approvals, ideally via a private approval workflow, and set expiry dates for guest accounts to ensure access is revoked after projects end."

Multi-Channel Guests (Option B) provide broader access than necessary, and manually inviting guests (Option C) does not scale well. Asking companies to upgrade (Option D) is unrealistic for scalable collaboration.

(Reference: Slack Administration Study Guide - Guest Management and External Collaboration)

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Slack domain claiming is:

"Only available on Enterprise Grid, allowing an organization to reserve its domain and prevent users from creating independent Slack workspaces with corporate emails."

Pro plan (A) cannot support domain claiming. EKM (B) secures encryption keys, unrelated to domain claiming. 2FA (D) enhances authentication but doesn’t block workspace creation.

(Reference: Slack Administration Study Guide - Domain Management on Enterprise Grid)

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Slack best practices recommend:

"For external users who need access to multiple channels but not the entire workspace, a Multi-Channel Guest account is the ideal solution."

Full member access (D) is inappropriate for external users. Slack Connect DMs (B) would not provide full channel collaboration. Single-Channel Guest (C) would limit the contractor unnecessarily.

(Reference: Slack Administration Study Guide - Managing Guest Accounts in Enterprise Grid)

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Slack’s Workflow Builder is designed to:

"Allow non-developers to automate routine tasks without writing code, support integrations with apps and services for enhanced workflows, and provide templates that users can customize."

While developers can use Workflow Builder, it is primarily aimed at non-technical users; developers usually prefer building custom apps or using Slack APIs.

(Reference: Slack Administration Study Guide - Workflow Builder Overview)

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Slack warns that:

"Having too many workspaces can create challenges with context switching, where users need to frequently switch between workspaces to find information, reducing efficiency. It also impacts scalability as the organization grows."

While admin and user management complexity (C) can exist, context-switching (D) is the most relevant and critical issue in multi-workspace designs like the one proposed.

(Reference: Slack Administration Study Guide - Enterprise Grid Design Best Practices)

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Slack recommends using an org-wide channel for announcements:

"An org-wide channel ensures that important updates reach every member across all workspaces. Bookmarking learning materials in the channel also provides members with easy access to ongoing resources and updates."

Options B and C place too much burden on members to seek out information. D is reactive (waiting for questions) rather than proactive enablement.

(Reference: Slack Administration Study Guide - Managing Change and Member Enablement)

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