| SII | Investments Inc 
| Others |
| SII | Scalable Information Infrastructure
| Others |
| SII | Schools Improvement Initiative
| Others |
| SII | Science Information Infrastructure
| Others |
| SII | Science Integration Institute
| Others |
| SII | Securities and Investment Institute
| Others |
| SII | Securities Industry Institute
| Others |
| SII | Security Industry Institute
| Others |
| SII | Security Institute of Ireland
| Others |
| SII | Seiko Instruments Inc
| Others |
| SII | Seiko Instruments, Inc.
| Others |
| SII | Self Inflicted Injuries
| Others |
| SII | Sensory Integration International
| Others |
| SII | Series Two
| Others |
| SII | Seriously Ill or Injured
| Others |
| SII | Seriously Impaired Imagination
| Others |
| SII | Serum Institute of India
| Medical, Research Center |
| SII | Service Independent Intercept
| Others |
| SII | Service Interval Indicator
| Others |
| SII | Servicio de Impuestos Internos
| Others |
| SII | Shipper Interest Insurance
| Others |
| SII | Silicon Image Inc.
| Others |
| SII | Simulated Iterator And Inquisitor
| Others |
| SII | Social Investment Initiative
| Others |
| SII | Solar Industries India Limited
| Company, Defence, Manufacturing |
| SII | Special Instruction Indicator
| Others |
| SII | Special Interest Items
| Others |
| SII | Speech Intelligibility Index
| Others |
| SII | Spinal Injuries Ireland
| Others |
| SII | Standards Institution of Israel
| Others |
| SII | Statement of Intelligence Interest
| Others |
| SII | Statistics and Its Interface
| Others |
| SII | Steico Industries, Inc.
| Others |
| SII | Stellar International Institute
| Others |
| SII | Strategic Investor Initiative
| Others |
| SII | Strengths Improvements and Insights
| Others |
| SII | Strengths, Improvements, And Insights
| Others |
| SII | Strong Interest Inventory
| Others |
| SII | Study of Instructional Improvement
| Others |
| SII | Successor In Interest
| Others |
| SII | Summary Injury Incidence
| Others |
| SII | Summary of Investment Information
| Others |
| SII | Sustainable Innovation Initiatives
| Others |
| SII | System Integrators, Inc.
| Others |
| SII | The Southern Industrial Institute
| Others |